Installing a cluster on vSphere in a restricted network with user-provisioned infrastructure

In OKD version 4.14, you can install a cluster on VMware vSphere infrastructure that you provision in a restricted network.

OKD supports deploying a cluster to a single VMware vCenter only. Deploying a cluster with machines/machine sets on multiple vCenters is not supported.

The steps for performing a user-provisioned infrastructure installation are provided as an example only. Installing a cluster with infrastructure you provide requires knowledge of the vSphere platform and the installation process of OKD. Use the user-provisioned infrastructure installation instructions as a guide; you are free to create the required resources through other methods.

Prerequisites

  • You reviewed details about the OKD installation and update processes.

  • You read the documentation on selecting a cluster installation method and preparing it for users.

  • You created a registry on your mirror host and obtained the imageContentSources data for your version of OKD.

    Because the installation media is on the mirror host, you can use that computer to complete all installation steps.

  • You provisioned persistent storage for your cluster. To deploy a private image registry, your storage must provide ReadWriteMany access modes.

  • Completing the installation requires that you upload the Fedora CoreOS (FCOS) OVA on vSphere hosts. The machine from which you complete this process requires access to port 443 on the vCenter and ESXi hosts. You verified that port 443 is accessible.

  • If you use a firewall, you confirmed with the administrator that port 443 is accessible. Control plane nodes must be able to reach vCenter and ESXi hosts on port 443 for the installation to succeed.

  • If you use a firewall and plan to use the Telemetry service, you configured the firewall to allow the sites that your cluster requires access to.

    Be sure to also review this site list if you are configuring a proxy.

About installations in restricted networks

In OKD 4.14, you can perform an installation that does not require an active connection to the internet to obtain software components. Restricted network installations can be completed using installer-provisioned infrastructure or user-provisioned infrastructure, depending on the cloud platform to which you are installing the cluster.

If you choose to perform a restricted network installation on a cloud platform, you still require access to its cloud APIs. Some cloud functions, like Amazon Web Service’s Route 53 DNS and IAM services, require internet access. Depending on your network, you might require less internet access for an installation on bare metal hardware, Nutanix, or on VMware vSphere.

To complete a restricted network installation, you must create a registry that mirrors the contents of the OpenShift image registry and contains the installation media. You can create this registry on a mirror host, which can access both the internet and your closed network, or by using other methods that meet your restrictions.

Because of the complexity of the configuration for user-provisioned installations, consider completing a standard user-provisioned infrastructure installation before you attempt a restricted network installation using user-provisioned infrastructure. Completing this test installation might make it easier to isolate and troubleshoot any issues that might arise during your installation in a restricted network.

Additional limits

Clusters in restricted networks have the following additional limitations and restrictions:

  • The ClusterVersion status includes an Unable to retrieve available updates error.

  • By default, you cannot use the contents of the Developer Catalog because you cannot access the required image stream tags.

VMware vSphere infrastructure requirements

You must install the OKD cluster on a VMware vSphere version 7.0 Update 2 or later instance that meets the requirements for the components that you use.

OKD version 4.14 supports VMware vSphere version 8.0.

You can host the VMware vSphere infrastructure on-premise or on a VMware Cloud Verified provider that meets the requirements outlined in the following tables:

Table 1. Version requirements for vSphere virtual environments
Virtual environment productRequired version

VMware virtual hardware

15 or later

vSphere ESXi hosts

7.0 Update 2 or later

vCenter host

7.0 Update 2 or later

You must ensure that the time on your ESXi hosts is synchronized before you install OKD. See Edit Time Configuration for a Host in the VMware documentation.

Table 2. Minimum supported vSphere version for VMware components
ComponentMinimum supported versionsDescription

Hypervisor

vSphere 7.0 Update 2 and later with virtual hardware version 15

This version is the minimum version that Fedora CoreOS (FCOS) supports. For more information about supported hardware on the latest version of Fedora that is compatible with FCOS, see Hardware on the Red Hat Customer Portal.

Storage with in-tree drivers

vSphere 7.0 Update 2 and later

This plugin creates vSphere storage by using the in-tree storage drivers for vSphere included in OKD.

Optional: Networking (NSX-T)

vSphere 7.0 Update 2 and later

vSphere 7.0 Update 2 is required for OKD. For more information about the compatibility of NSX and OKD, see the Release Notes section of VMware’s NSX container plugin documentation.

To ensure the best performance conditions for your cluster workloads that operate on Oracle® Cloud Infrastructure (OCI) and on the Oracle® Cloud VMware Solution (OCVS) service, ensure volume performance units (VPUs) for your block volume are sized for your workloads.

The following list provides some guidance in selecting the VPUs needed for specific performance needs:

  • Test or proof of concept environment: 100 GB, and 20 to 30 VPUs.

  • Base-production environment: 500 GB, and 60 VPUs.

  • Heavy-use production environment: More than 500 GB, and 100 or more VPUs.

Consider allocating additional VPUs to give enough capacity for updates and scaling activities. See Block Volume Performance Levels in the Oracle documentation.

VMware vSphere CSI Driver Operator requirements

To install the vSphere CSI Driver Operator, the following requirements must be met:

  • VMware vSphere version 7.0 Update 2 or later

  • vCenter 7.0 Update 2 or later

  • Virtual machines of hardware version 15 or later

  • No third-party vSphere CSI driver already installed in the cluster

If a third-party vSphere CSI driver is present in the cluster, OKD does not overwrite it. The presence of a third-party vSphere CSI driver prevents OKD from updating to OKD 4.13 or later.

The VMware vSphere CSI Driver Operator is supported only on clusters deployed with platform: vsphere in the installation manifest.

Additional resources

Requirements for a cluster with user-provisioned infrastructure

For a cluster that contains user-provisioned infrastructure, you must deploy all of the required machines.

This section describes the requirements for deploying OKD on user-provisioned infrastructure.

vCenter requirements

Before you install an OKD cluster on your vCenter that uses infrastructure that you provided, you must prepare your environment.

Required vCenter account privileges

To install an OKD cluster in a vCenter, your vSphere account must include privileges for reading and creating the required resources. Using an account that has global administrative privileges is the simplest way to access all of the necessary permissions.

Roles and privileges required for installation in vSphere API

vSphere object for roleWhen requiredRequired privileges in vSphere API

vSphere vCenter

Always

Cns.Searchable
InventoryService.Tagging.AttachTag
InventoryService.Tagging.CreateCategory
InventoryService.Tagging.CreateTag
InventoryService.Tagging.DeleteCategory
InventoryService.Tagging.DeleteTag
InventoryService.Tagging.EditCategory
InventoryService.Tagging.EditTag
Sessions.ValidateSession
StorageProfile.Update
StorageProfile.View

vSphere vCenter Cluster

If VMs will be created in the cluster root

Host.Config.Storage
Resource.AssignVMToPool
VApp.AssignResourcePool
VApp.Import
VirtualMachine.Config.AddNewDisk

vSphere vCenter Resource Pool

If an existing resource pool is provided

Host.Config.Storage
Resource.AssignVMToPool
VApp.AssignResourcePool
VApp.Import
VirtualMachine.Config.AddNewDisk

vSphere Datastore

Always

Datastore.AllocateSpace
Datastore.Browse
Datastore.FileManagement
InventoryService.Tagging.ObjectAttachable

vSphere Port Group

Always

Network.Assign

Virtual Machine Folder

Always

InventoryService.Tagging.ObjectAttachable
Resource.AssignVMToPool
VApp.Import
VirtualMachine.Config.AddExistingDisk
VirtualMachine.Config.AddNewDisk
VirtualMachine.Config.AddRemoveDevice
VirtualMachine.Config.AdvancedConfig
VirtualMachine.Config.Annotation
VirtualMachine.Config.CPUCount
VirtualMachine.Config.DiskExtend
VirtualMachine.Config.DiskLease
VirtualMachine.Config.EditDevice
VirtualMachine.Config.Memory
VirtualMachine.Config.RemoveDisk
VirtualMachine.Config.Rename
VirtualMachine.Config.ResetGuestInfo
VirtualMachine.Config.Resource
VirtualMachine.Config.Settings
VirtualMachine.Config.UpgradeVirtualHardware
VirtualMachine.Interact.GuestControl
VirtualMachine.Interact.PowerOff
VirtualMachine.Interact.PowerOn
VirtualMachine.Interact.Reset
VirtualMachine.Inventory.Create
VirtualMachine.Inventory.CreateFromExisting
VirtualMachine.Inventory.Delete
VirtualMachine.Provisioning.Clone
VirtualMachine.Provisioning.MarkAsTemplate
VirtualMachine.Provisioning.DeployTemplate

vSphere vCenter Datacenter

If the installation program creates the virtual machine folder. For UPI, VirtualMachine.Inventory.Create and VirtualMachine.Inventory.Delete privileges are optional if your cluster does not use the Machine API.

InventoryService.Tagging.ObjectAttachable
Resource.AssignVMToPool
VApp.Import
VirtualMachine.Config.AddExistingDisk
VirtualMachine.Config.AddNewDisk
VirtualMachine.Config.AddRemoveDevice
VirtualMachine.Config.AdvancedConfig
VirtualMachine.Config.Annotation
VirtualMachine.Config.CPUCount
VirtualMachine.Config.DiskExtend
VirtualMachine.Config.DiskLease
VirtualMachine.Config.EditDevice
VirtualMachine.Config.Memory
VirtualMachine.Config.RemoveDisk
VirtualMachine.Config.Rename
VirtualMachine.Config.ResetGuestInfo
VirtualMachine.Config.Resource
VirtualMachine.Config.Settings
VirtualMachine.Config.UpgradeVirtualHardware
VirtualMachine.Interact.GuestControl
VirtualMachine.Interact.PowerOff
VirtualMachine.Interact.PowerOn
VirtualMachine.Interact.Reset
VirtualMachine.Inventory.Create
VirtualMachine.Inventory.CreateFromExisting
VirtualMachine.Inventory.Delete
VirtualMachine.Provisioning.Clone
VirtualMachine.Provisioning.DeployTemplate
VirtualMachine.Provisioning.MarkAsTemplate
Folder.Create
Folder.Delete

Roles and privileges required for installation in vCenter graphical user interface (GUI)

vSphere object for roleWhen requiredRequired privileges in vCenter GUI

vSphere vCenter

Always

Cns.Searchable
“vSphere Tagging”.”Assign or Unassign vSphere Tag”
“vSphere Tagging”.”Create vSphere Tag Category”
“vSphere Tagging”.”Create vSphere Tag”
vSphere Tagging”.”Delete vSphere Tag Category”
“vSphere Tagging”.”Delete vSphere Tag”
“vSphere Tagging”.”Edit vSphere Tag Category”
“vSphere Tagging”.”Edit vSphere Tag”
Sessions.”Validate session”
“Profile-driven storage”.”Profile-driven storage update”
“Profile-driven storage”.”Profile-driven storage view”

vSphere vCenter Cluster

If VMs will be created in the cluster root

Host.Configuration.”Storage partition configuration”
Resource.”Assign virtual machine to resource pool”
VApp.”Assign resource pool”
VApp.Import
“Virtual machine”.”Change Configuration”.”Add new disk”

vSphere vCenter Resource Pool

If an existing resource pool is provided

Host.Configuration.”Storage partition configuration”
Resource.”Assign virtual machine to resource pool”
VApp.”Assign resource pool”
VApp.Import
“Virtual machine”.”Change Configuration”.”Add new disk”

vSphere Datastore

Always

Datastore.”Allocate space”
Datastore.”Browse datastore”
Datastore.”Low level file operations”
“vSphere Tagging”.”Assign or Unassign vSphere Tag on Object”

vSphere Port Group

Always

Network.”Assign network”

Virtual Machine Folder

Always

“vSphere Tagging”.”Assign or Unassign vSphere Tag on Object”
Resource.”Assign virtual machine to resource pool”
VApp.Import
“Virtual machine”.”Change Configuration”.”Add existing disk”
“Virtual machine”.”Change Configuration”.”Add new disk”
“Virtual machine”.”Change Configuration”.”Add or remove device”
“Virtual machine”.”Change Configuration”.”Advanced configuration”
“Virtual machine”.”Change Configuration”.”Set annotation”
“Virtual machine”.”Change Configuration”.”Change CPU count”
“Virtual machine”.”Change Configuration”.”Extend virtual disk”
“Virtual machine”.”Change Configuration”.”Acquire disk lease”
“Virtual machine”.”Change Configuration”.”Modify device settings”
“Virtual machine”.”Change Configuration”.”Change Memory”
“Virtual machine”.”Change Configuration”.”Remove disk”
“Virtual machine”.”Change Configuration”.Rename
“Virtual machine”.”Change Configuration”.”Reset guest information”
“Virtual machine”.”Change Configuration”.”Change resource”
“Virtual machine”.”Change Configuration”.”Change Settings”
“Virtual machine”.”Change Configuration”.”Upgrade virtual machine compatibility”
“Virtual machine”.Interaction.”Guest operating system management by VIX API”
“Virtual machine”.Interaction.”Power off”
“Virtual machine”.Interaction.”Power on”
“Virtual machine”.Interaction.Reset
“Virtual machine”.”Edit Inventory”.”Create new”
“Virtual machine”.”Edit Inventory”.”Create from existing”
“Virtual machine”.”Edit Inventory”.”Remove”
“Virtual machine”.Provisioning.”Clone virtual machine”
“Virtual machine”.Provisioning.”Mark as template”
“Virtual machine”.Provisioning.”Deploy template”

vSphere vCenter Datacenter

If the installation program creates the virtual machine folder. For UPI, VirtualMachine.Inventory.Create and VirtualMachine.Inventory.Delete privileges are optional if your cluster does not use the Machine API.

“vSphere Tagging”.”Assign or Unassign vSphere Tag on Object”
Resource.”Assign virtual machine to resource pool”
VApp.Import
“Virtual machine”.”Change Configuration”.”Add existing disk”
“Virtual machine”.”Change Configuration”.”Add new disk”
“Virtual machine”.”Change Configuration”.”Add or remove device”
“Virtual machine”.”Change Configuration”.”Advanced configuration”
“Virtual machine”.”Change Configuration”.”Set annotation”
“Virtual machine”.”Change Configuration”.”Change CPU count”
“Virtual machine”.”Change Configuration”.”Extend virtual disk”
“Virtual machine”.”Change Configuration”.”Acquire disk lease”
“Virtual machine”.”Change Configuration”.”Modify device settings”
“Virtual machine”.”Change Configuration”.”Change Memory”
“Virtual machine”.”Change Configuration”.”Remove disk”
“Virtual machine”.”Change Configuration”.Rename
“Virtual machine”.”Change Configuration”.”Reset guest information”
“Virtual machine”.”Change Configuration”.”Change resource”
“Virtual machine”.”Change Configuration”.”Change Settings”
“Virtual machine”.”Change Configuration”.”Upgrade virtual machine compatibility”
“Virtual machine”.Interaction.”Guest operating system management by VIX API”
“Virtual machine”.Interaction.”Power off”
“Virtual machine”.Interaction.”Power on”
“Virtual machine”.Interaction.Reset
“Virtual machine”.”Edit Inventory”.”Create new”
“Virtual machine”.”Edit Inventory”.”Create from existing”
“Virtual machine”.”Edit Inventory”.”Remove”
“Virtual machine”.Provisioning.”Clone virtual machine”
“Virtual machine”.Provisioning.”Deploy template”
“Virtual machine”.Provisioning.”Mark as template”
Folder.”Create folder”
Folder.”Delete folder”

Additionally, the user requires some ReadOnly permissions, and some of the roles require permission to propogate the permissions to child objects. These settings vary depending on whether or not you install the cluster into an existing folder.

Required permissions and propagation settings

vSphere objectWhen requiredPropagate to childrenPermissions required

vSphere vCenter

Always

False

Listed required privileges

vSphere vCenter Datacenter

Existing folder

False

ReadOnly permission

Installation program creates the folder

True

Listed required privileges

vSphere vCenter Cluster

Existing resource pool

False

ReadOnly permission

VMs in cluster root

True

Listed required privileges

vSphere vCenter Datastore

Always

False

Listed required privileges

vSphere Switch

Always

False

ReadOnly permission

vSphere Port Group

Always

False

Listed required privileges

vSphere vCenter Virtual Machine Folder

Existing folder

True

Listed required privileges

vSphere vCenter Resource Pool

Existing resource pool

True

Listed required privileges

For more information about creating an account with only the required privileges, see vSphere Permissions and User Management Tasks in the vSphere documentation.

Using OKD with vMotion

If you intend on using vMotion in your vSphere environment, consider the following before installing an OKD cluster.

  • OKD generally supports compute-only vMotion. Using Storage vMotion can cause issues and is not supported.

    To help ensure the uptime of your compute and control plane nodes, it is recommended that you follow the VMware best practices for vMotion. It is also recommended to use VMware anti-affinity rules to improve the availability of OKD during maintenance or hardware issues.

    For more information about vMotion and anti-affinity rules, see the VMware vSphere documentation for vMotion networking requirements and VM anti-affinity rules.

  • If you are using vSphere volumes in your pods, migrating a VM across datastores either manually or through Storage vMotion causes, invalid references within OKD persistent volume (PV) objects. These references prevent affected pods from starting up and can result in data loss.

  • Similarly, OKD does not support selective migration of VMDKs across datastores, using datastore clusters for VM provisioning or for dynamic or static provisioning of PVs, or using a datastore that is part of a datastore cluster for dynamic or static provisioning of PVs.

    You can specify the path of any datastore that exists in a datastore cluster. By default, Storage Distributed Resource Scheduler (SDRS), which uses Storage vMotion, is automatically enabled for a datastore cluster. Red Hat does not support Storage vMotion, so you must disable Storage DRS to avoid data loss issues for your OKD cluster.

    If you must specify VMs across multiple datastores, use a datastore object to specify a failure domain in your cluster’s install-config.yaml configuration file. For more information, see “VMware vSphere region and zone enablement”.

Cluster resources

When you deploy an OKD cluster that uses infrastructure that you provided, you must create the following resources in your vCenter instance:

  • 1 Folder

  • 1 Tag category

  • 1 Tag

  • Virtual machines:

    • 1 template

    • 1 temporary bootstrap node

    • 3 control plane nodes

    • 3 compute machines

Although these resources use 856 GB of storage, the bootstrap node is destroyed during the cluster installation process. A minimum of 800 GB of storage is required to use a standard cluster.

If you deploy more compute machines, the OKD cluster will use more storage.

Cluster limits

Available resources vary between clusters. The number of possible clusters within a vCenter is limited primarily by available storage space and any limitations on the number of required resources. Be sure to consider both limitations to the vCenter resources that the cluster creates and the resources that you require to deploy a cluster, such as IP addresses and networks.

Networking requirements

Use Dynamic Host Configuration Protocol (DHCP) for the network and ensure that the DHCP server is configured to provide persistent IP addresses to the cluster machines.

You do not need to use the DHCP for the network if you want to provision nodes with static IP addresses.

Configure the default gateway to use the DHCP server. All nodes must be in the same VLAN. You cannot scale the cluster using a second VLAN as a Day 2 operation.

You must use the Dynamic Host Configuration Protocol (DHCP) for the network and ensure that the DHCP server is configured to provide persistent IP addresses to the cluster machines. In the DHCP lease, you must configure the DHCP to use the default gateway. All nodes must be in the same VLAN. You cannot scale the cluster using a second VLAN as a Day 2 operation.

Additionally, you must create the following networking resources before you install the OKD cluster:

It is recommended that each OKD node in the cluster must have access to a Network Time Protocol (NTP) server that is discoverable via DHCP. Installation is possible without an NTP server. However, asynchronous server clocks will cause errors, which NTP server prevents.

Required IP Addresses
DNS records

You must create DNS records for two static IP addresses in the appropriate DNS server for the vCenter instance that hosts your OKD cluster. In each record, <cluster_name> is the cluster name and <base_domain> is the cluster base domain that you specify when you install the cluster. A complete DNS record takes the form: <component>.<cluster_name>.<base_domain>..

Table 3. Required DNS records
ComponentRecordDescription

API VIP

api.<cluster_name>.<base_domain>.

This DNS A/AAAA or CNAME record must point to the load balancer for the control plane machines. This record must be resolvable by both clients external to the cluster and from all the nodes within the cluster.

Ingress VIP

*.apps.<cluster_name>.<base_domain>.

A wildcard DNS A/AAAA or CNAME record that points to the load balancer that targets the machines that run the Ingress router pods, which are the worker nodes by default. This record must be resolvable by both clients external to the cluster and from all the nodes within the cluster.

Additional resources

Required machines for cluster installation

The smallest OKD clusters require the following hosts:

Table 4. Minimum required hosts
HostsDescription

One temporary bootstrap machine

The cluster requires the bootstrap machine to deploy the OKD cluster on the three control plane machines. You can remove the bootstrap machine after you install the cluster.

Three control plane machines

The control plane machines run the Kubernetes and OKD services that form the control plane.

At least two compute machines, which are also known as worker machines.

The workloads requested by OKD users run on the compute machines.

To maintain high availability of your cluster, use separate physical hosts for these cluster machines.

The bootstrap and control plane machines must use Fedora CoreOS (FCOS) as the operating system. However, the compute machines can choose between Fedora CoreOS (FCOS), Fedora 8.6, Fedora 8.7, or Fedora 8.8.

See Red Hat Enterprise Linux technology capabilities and limits.

Minimum resource requirements for cluster installation

Each cluster machine must meet the following minimum requirements:

Table 5. Minimum resource requirements
MachineOperating SystemvCPU [1]Virtual RAMStorageInput/Output Per Second (IOPS)[2]

Bootstrap

FCOS

4

16 GB

100 GB

300

Control plane

FCOS

4

16 GB

100 GB

300

Compute

FCOS

2

8 GB

100 GB

300

  1. One vCPU is equivalent to one physical core when simultaneous multithreading (SMT), or hyperthreading, is not enabled. When enabled, use the following formula to calculate the corresponding ratio: (threads per core × cores) × sockets = vCPUs.

  2. OKD and Kubernetes are sensitive to disk performance, and faster storage is recommended, particularly for etcd on the control plane nodes which require a 10 ms p99 fsync duration. Note that on many cloud platforms, storage size and IOPS scale together, so you might need to over-allocate storage volume to obtain sufficient performance.

  3. As with all user-provisioned installations, if you choose to use Fedora compute machines in your cluster, you take responsibility for all operating system life cycle management and maintenance, including performing system updates, applying patches, and completing all other required tasks. Use of Fedora 7 compute machines is deprecated and has been removed in OKD 4.10 and later.

If an instance type for your platform meets the minimum requirements for cluster machines, it is supported to use in OKD.

Additional resources

Requirements for encrypting virtual machines

You can encrypt your virtual machines prior to installing OKD 4.14 by meeting the following requirements.

When you deploy the OVF template in the section titled “Installing RHCOS and starting the OpenShift Container Platform bootstrap process”, select the option to “Encrypt this virtual machine” when you are selecting storage for the OVF template. After completing cluster installation, create a storage class that uses the encryption storage policy you used to encrypt the virtual machines.

Additional resources

Certificate signing requests management

Because your cluster has limited access to automatic machine management when you use infrastructure that you provision, you must provide a mechanism for approving cluster certificate signing requests (CSRs) after installation. The kube-controller-manager only approves the kubelet client CSRs. The machine-approver cannot guarantee the validity of a serving certificate that is requested by using kubelet credentials because it cannot confirm that the correct machine issued the request. You must determine and implement a method of verifying the validity of the kubelet serving certificate requests and approving them.

Networking requirements for user-provisioned infrastructure

All the Fedora CoreOS (FCOS) machines require networking to be configured in initramfs during boot to fetch their Ignition config files.

During the initial boot, the machines require an IP address configuration that is set either through a DHCP server or statically by providing the required boot options. After a network connection is established, the machines download their Ignition config files from an HTTP or HTTPS server. The Ignition config files are then used to set the exact state of each machine. The Machine Config Operator completes more changes to the machines, such as the application of new certificates or keys, after installation.

It is recommended to use a DHCP server for long-term management of the cluster machines. Ensure that the DHCP server is configured to provide persistent IP addresses, DNS server information, and hostnames to the cluster machines.

If a DHCP service is not available for your user-provisioned infrastructure, you can instead provide the IP networking configuration and the address of the DNS server to the nodes at FCOS install time. These can be passed as boot arguments if you are installing from an ISO image. See the Installing FCOS and starting the OKD bootstrap process section for more information about static IP provisioning and advanced networking options.

The Kubernetes API server must be able to resolve the node names of the cluster machines. If the API servers and worker nodes are in different zones, you can configure a default DNS search zone to allow the API server to resolve the node names. Another supported approach is to always refer to hosts by their fully-qualified domain names in both the node objects and all DNS requests.

Setting the cluster node hostnames through DHCP

On Fedora CoreOS (FCOS) machines, the hostname is set through NetworkManager. By default, the machines obtain their hostname through DHCP. If the hostname is not provided by DHCP, set statically through kernel arguments, or another method, it is obtained through a reverse DNS lookup. Reverse DNS lookup occurs after the network has been initialized on a node and can take time to resolve. Other system services can start prior to this and detect the hostname as localhost or similar. You can avoid this by using DHCP to provide the hostname for each cluster node.

Additionally, setting the hostnames through DHCP can bypass any manual DNS record name configuration errors in environments that have a DNS split-horizon implementation.

Network connectivity requirements

You must configure the network connectivity between machines to allow OKD cluster components to communicate. Each machine must be able to resolve the hostnames of all other machines in the cluster.

This section provides details about the ports that are required.

In connected OKD environments, all nodes are required to have internet access to pull images for platform containers and provide telemetry data to Red Hat.

Table 6. Ports used for all-machine to all-machine communications
ProtocolPortDescription

ICMP

N/A

Network reachability tests

TCP

1936

Metrics

9000-9999

Host level services, including the node exporter on ports 9100-9101 and the Cluster Version Operator on port 9099.

10250-10259

The default ports that Kubernetes reserves

10256

openshift-sdn

UDP

4789

VXLAN

6081

Geneve

9000-9999

Host level services, including the node exporter on ports 9100-9101.

500

IPsec IKE packets

4500

IPsec NAT-T packets

TCP/UDP

30000-32767

Kubernetes node port

ESP

N/A

IPsec Encapsulating Security Payload (ESP)

Table 7. Ports used for all-machine to control plane communications
ProtocolPortDescription

TCP

6443

Kubernetes API

Table 8. Ports used for control plane machine to control plane machine communications
ProtocolPortDescription

TCP

2379-2380

etcd server and peer ports

Ethernet adaptor hardware address requirements

When provisioning VMs for the cluster, the ethernet interfaces configured for each VM must use a MAC address from the VMware Organizationally Unique Identifier (OUI) allocation ranges:

  • 00:05:69:00:00:00 to 00:05:69:FF:FF:FF

  • 00:0c:29:00:00:00 to 00:0c:29:FF:FF:FF

  • 00:1c:14:00:00:00 to 00:1c:14:FF:FF:FF

  • 00:50:56:00:00:00 to 00:50:56:3F:FF:FF

If a MAC address outside the VMware OUI is used, the cluster installation will not succeed.

NTP configuration for user-provisioned infrastructure

OKD clusters are configured to use a public Network Time Protocol (NTP) server by default. If you want to use a local enterprise NTP server, or if your cluster is being deployed in a disconnected network, you can configure the cluster to use a specific time server. For more information, see the documentation for Configuring chrony time service.

If a DHCP server provides NTP server information, the chrony time service on the Fedora CoreOS (FCOS) machines read the information and can sync the clock with the NTP servers.

Additional resources

User-provisioned DNS requirements

In OKD deployments, DNS name resolution is required for the following components:

  • The Kubernetes API

  • The OKD application wildcard

  • The bootstrap, control plane, and compute machines

Reverse DNS resolution is also required for the Kubernetes API, the bootstrap machine, the control plane machines, and the compute machines.

DNS A/AAAA or CNAME records are used for name resolution and PTR records are used for reverse name resolution. The reverse records are important because Fedora CoreOS (FCOS) uses the reverse records to set the hostnames for all the nodes, unless the hostnames are provided by DHCP. Additionally, the reverse records are used to generate the certificate signing requests (CSR) that OKD needs to operate.

It is recommended to use a DHCP server to provide the hostnames to each cluster node. See the DHCP recommendations for user-provisioned infrastructure section for more information.

The following DNS records are required for a user-provisioned OKD cluster and they must be in place before installation. In each record, <cluster_name> is the cluster name and <base_domain> is the base domain that you specify in the install-config.yaml file. A complete DNS record takes the form: <component>.<cluster_name>.<base_domain>..

Table 9. Required DNS records
ComponentRecordDescription

Kubernetes API

api.<cluster_name>.<base_domain>.

A DNS A/AAAA or CNAME record, and a DNS PTR record, to identify the API load balancer. These records must be resolvable by both clients external to the cluster and from all the nodes within the cluster.

api-int.<cluster_name>.<base_domain>.

A DNS A/AAAA or CNAME record, and a DNS PTR record, to internally identify the API load balancer. These records must be resolvable from all the nodes within the cluster.

The API server must be able to resolve the worker nodes by the hostnames that are recorded in Kubernetes. If the API server cannot resolve the node names, then proxied API calls can fail, and you cannot retrieve logs from pods.

Routes

*.apps.<cluster_name>.<base_domain>.

A wildcard DNS A/AAAA or CNAME record that refers to the application ingress load balancer. The application ingress load balancer targets the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default. These records must be resolvable by both clients external to the cluster and from all the nodes within the cluster.

For example, console-openshift-console.apps.<cluster_name>.<base_domain> is used as a wildcard route to the OKD console.

Bootstrap machine

bootstrap.<cluster_name>.<base_domain>.

A DNS A/AAAA or CNAME record, and a DNS PTR record, to identify the bootstrap machine. These records must be resolvable by the nodes within the cluster.

Control plane machines

<master><n>.<cluster_name>.<base_domain>.

DNS A/AAAA or CNAME records and DNS PTR records to identify each machine for the control plane nodes. These records must be resolvable by the nodes within the cluster.

Compute machines

<worker><n>.<cluster_name>.<base_domain>.

DNS A/AAAA or CNAME records and DNS PTR records to identify each machine for the worker nodes. These records must be resolvable by the nodes within the cluster.

In OKD 4.4 and later, you do not need to specify etcd host and SRV records in your DNS configuration.

You can use the dig command to verify name and reverse name resolution. See the section on Validating DNS resolution for user-provisioned infrastructure for detailed validation steps.

Example DNS configuration for user-provisioned clusters

This section provides A and PTR record configuration samples that meet the DNS requirements for deploying OKD on user-provisioned infrastructure. The samples are not meant to provide advice for choosing one DNS solution over another.

In the examples, the cluster name is ocp4 and the base domain is example.com.

Example DNS A record configuration for a user-provisioned cluster

The following example is a BIND zone file that shows sample A records for name resolution in a user-provisioned cluster.

Sample DNS zone database

  1. $TTL 1W
  2. @ IN SOA ns1.example.com. root (
  3. 2019070700 ; serial
  4. 3H ; refresh (3 hours)
  5. 30M ; retry (30 minutes)
  6. 2W ; expiry (2 weeks)
  7. 1W ) ; minimum (1 week)
  8. IN NS ns1.example.com.
  9. IN MX 10 smtp.example.com.
  10. ;
  11. ;
  12. ns1.example.com. IN A 192.168.1.5
  13. smtp.example.com. IN A 192.168.1.5
  14. ;
  15. helper.example.com. IN A 192.168.1.5
  16. helper.ocp4.example.com. IN A 192.168.1.5
  17. ;
  18. api.ocp4.example.com. IN A 192.168.1.5 (1)
  19. api-int.ocp4.example.com. IN A 192.168.1.5 (2)
  20. ;
  21. *.apps.ocp4.example.com. IN A 192.168.1.5 (3)
  22. ;
  23. bootstrap.ocp4.example.com. IN A 192.168.1.96 (4)
  24. ;
  25. master0.ocp4.example.com. IN A 192.168.1.97 (5)
  26. master1.ocp4.example.com. IN A 192.168.1.98 (5)
  27. master2.ocp4.example.com. IN A 192.168.1.99 (5)
  28. ;
  29. worker0.ocp4.example.com. IN A 192.168.1.11 (6)
  30. worker1.ocp4.example.com. IN A 192.168.1.7 (6)
  31. ;
  32. ;EOF
1Provides name resolution for the Kubernetes API. The record refers to the IP address of the API load balancer.
2Provides name resolution for the Kubernetes API. The record refers to the IP address of the API load balancer and is used for internal cluster communications.
3Provides name resolution for the wildcard routes. The record refers to the IP address of the application ingress load balancer. The application ingress load balancer targets the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default.

In the example, the same load balancer is used for the Kubernetes API and application ingress traffic. In production scenarios, you can deploy the API and application ingress load balancers separately so that you can scale the load balancer infrastructure for each in isolation.

4Provides name resolution for the bootstrap machine.
5Provides name resolution for the control plane machines.
6Provides name resolution for the compute machines.

Example DNS PTR record configuration for a user-provisioned cluster

The following example BIND zone file shows sample PTR records for reverse name resolution in a user-provisioned cluster.

Sample DNS zone database for reverse records

  1. $TTL 1W
  2. @ IN SOA ns1.example.com. root (
  3. 2019070700 ; serial
  4. 3H ; refresh (3 hours)
  5. 30M ; retry (30 minutes)
  6. 2W ; expiry (2 weeks)
  7. 1W ) ; minimum (1 week)
  8. IN NS ns1.example.com.
  9. ;
  10. 5.1.168.192.in-addr.arpa. IN PTR api.ocp4.example.com. (1)
  11. 5.1.168.192.in-addr.arpa. IN PTR api-int.ocp4.example.com. (2)
  12. ;
  13. 96.1.168.192.in-addr.arpa. IN PTR bootstrap.ocp4.example.com. (3)
  14. ;
  15. 97.1.168.192.in-addr.arpa. IN PTR master0.ocp4.example.com. (4)
  16. 98.1.168.192.in-addr.arpa. IN PTR master1.ocp4.example.com. (4)
  17. 99.1.168.192.in-addr.arpa. IN PTR master2.ocp4.example.com. (4)
  18. ;
  19. 11.1.168.192.in-addr.arpa. IN PTR worker0.ocp4.example.com. (5)
  20. 7.1.168.192.in-addr.arpa. IN PTR worker1.ocp4.example.com. (5)
  21. ;
  22. ;EOF
1Provides reverse DNS resolution for the Kubernetes API. The PTR record refers to the record name of the API load balancer.
2Provides reverse DNS resolution for the Kubernetes API. The PTR record refers to the record name of the API load balancer and is used for internal cluster communications.
3Provides reverse DNS resolution for the bootstrap machine.
4Provides reverse DNS resolution for the control plane machines.
5Provides reverse DNS resolution for the compute machines.

A PTR record is not required for the OKD application wildcard.

Load balancing requirements for user-provisioned infrastructure

Before you install OKD, you must provision the API and application Ingress load balancing infrastructure. In production scenarios, you can deploy the API and application Ingress load balancers separately so that you can scale the load balancer infrastructure for each in isolation.

If you want to deploy the API and application Ingress load balancers with a Fedora instance, you must purchase the Fedora subscription separately.

The load balancing infrastructure must meet the following requirements:

  1. API load balancer: Provides a common endpoint for users, both human and machine, to interact with and configure the platform. Configure the following conditions:

    • Layer 4 load balancing only. This can be referred to as Raw TCP, SSL Passthrough, or SSL Bridge mode. If you use SSL Bridge mode, you must enable Server Name Indication (SNI) for the API routes.

    • A stateless load balancing algorithm. The options vary based on the load balancer implementation.

    Do not configure session persistence for an API load balancer. Configuring session persistence for a Kubernetes API server might cause performance issues from excess application traffic for your OKD cluster and the Kubernetes API that runs inside the cluster.

    Configure the following ports on both the front and back of the load balancers:

    Table 10. API load balancer
    PortBack-end machines (pool members)InternalExternalDescription

    6443

    Bootstrap and control plane. You remove the bootstrap machine from the load balancer after the bootstrap machine initializes the cluster control plane. You must configure the /readyz endpoint for the API server health check probe.

    X

    X

    Kubernetes API server

    22623

    Bootstrap and control plane. You remove the bootstrap machine from the load balancer after the bootstrap machine initializes the cluster control plane.

    X

    Machine config server

    The load balancer must be configured to take a maximum of 30 seconds from the time the API server turns off the /readyz endpoint to the removal of the API server instance from the pool. Within the time frame after /readyz returns an error or becomes healthy, the endpoint must have been removed or added. Probing every 5 or 10 seconds, with two successful requests to become healthy and three to become unhealthy, are well-tested values.

  2. Application Ingress load balancer: Provides an ingress point for application traffic flowing in from outside the cluster. A working configuration for the Ingress router is required for an OKD cluster.

    Configure the following conditions:

    • Layer 4 load balancing only. This can be referred to as Raw TCP, SSL Passthrough, or SSL Bridge mode. If you use SSL Bridge mode, you must enable Server Name Indication (SNI) for the ingress routes.

    • A connection-based or session-based persistence is recommended, based on the options available and types of applications that will be hosted on the platform.

    If the true IP address of the client can be seen by the application Ingress load balancer, enabling source IP-based session persistence can improve performance for applications that use end-to-end TLS encryption.

    Configure the following ports on both the front and back of the load balancers:

    Table 11. Application Ingress load balancer
    PortBack-end machines (pool members)InternalExternalDescription

    443

    The machines that run the Ingress Controller pods, compute, or worker, by default.

    X

    X

    HTTPS traffic

    80

    The machines that run the Ingress Controller pods, compute, or worker, by default.

    X

    X

    HTTP traffic

    If you are deploying a three-node cluster with zero compute nodes, the Ingress Controller pods run on the control plane nodes. In three-node cluster deployments, you must configure your application Ingress load balancer to route HTTP and HTTPS traffic to the control plane nodes.

Example load balancer configuration for user-provisioned clusters

This section provides an example API and application Ingress load balancer configuration that meets the load balancing requirements for user-provisioned clusters. The sample is an /etc/haproxy/haproxy.cfg configuration for an HAProxy load balancer. The example is not meant to provide advice for choosing one load balancing solution over another.

In the example, the same load balancer is used for the Kubernetes API and application ingress traffic. In production scenarios, you can deploy the API and application ingress load balancers separately so that you can scale the load balancer infrastructure for each in isolation.

If you are using HAProxy as a load balancer and SELinux is set to enforcing, you must ensure that the HAProxy service can bind to the configured TCP port by running setsebool -P haproxy_connect_any=1.

Sample API and application Ingress load balancer configuration

  1. global
  2. log 127.0.0.1 local2
  3. pidfile /var/run/haproxy.pid
  4. maxconn 4000
  5. daemon
  6. defaults
  7. mode http
  8. log global
  9. option dontlognull
  10. option http-server-close
  11. option redispatch
  12. retries 3
  13. timeout http-request 10s
  14. timeout queue 1m
  15. timeout connect 10s
  16. timeout client 1m
  17. timeout server 1m
  18. timeout http-keep-alive 10s
  19. timeout check 10s
  20. maxconn 3000
  21. listen api-server-6443 (1)
  22. bind *:6443
  23. mode tcp
  24. server bootstrap bootstrap.ocp4.example.com:6443 check inter 1s backup (2)
  25. server master0 master0.ocp4.example.com:6443 check inter 1s
  26. server master1 master1.ocp4.example.com:6443 check inter 1s
  27. server master2 master2.ocp4.example.com:6443 check inter 1s
  28. listen machine-config-server-22623 (3)
  29. bind *:22623
  30. mode tcp
  31. server bootstrap bootstrap.ocp4.example.com:22623 check inter 1s backup (2)
  32. server master0 master0.ocp4.example.com:22623 check inter 1s
  33. server master1 master1.ocp4.example.com:22623 check inter 1s
  34. server master2 master2.ocp4.example.com:22623 check inter 1s
  35. listen ingress-router-443 (4)
  36. bind *:443
  37. mode tcp
  38. balance source
  39. server worker0 worker0.ocp4.example.com:443 check inter 1s
  40. server worker1 worker1.ocp4.example.com:443 check inter 1s
  41. listen ingress-router-80 (5)
  42. bind *:80
  43. mode tcp
  44. balance source
  45. server worker0 worker0.ocp4.example.com:80 check inter 1s
  46. server worker1 worker1.ocp4.example.com:80 check inter 1s
1Port 6443 handles the Kubernetes API traffic and points to the control plane machines.
2The bootstrap entries must be in place before the OKD cluster installation and they must be removed after the bootstrap process is complete.
3Port 22623 handles the machine config server traffic and points to the control plane machines.
4Port 443 handles the HTTPS traffic and points to the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default.
5Port 80 handles the HTTP traffic and points to the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default.

If you are deploying a three-node cluster with zero compute nodes, the Ingress Controller pods run on the control plane nodes. In three-node cluster deployments, you must configure your application Ingress load balancer to route HTTP and HTTPS traffic to the control plane nodes.

If you are using HAProxy as a load balancer, you can check that the haproxy process is listening on ports 6443, 22623, 443, and 80 by running netstat -nltupe on the HAProxy node.

Preparing the user-provisioned infrastructure

Before you install OKD on user-provisioned infrastructure, you must prepare the underlying infrastructure.

This section provides details about the high-level steps required to set up your cluster infrastructure in preparation for an OKD installation. This includes configuring IP networking and network connectivity for your cluster nodes, enabling the required ports through your firewall, and setting up the required DNS and load balancing infrastructure.

After preparation, your cluster infrastructure must meet the requirements outlined in the Requirements for a cluster with user-provisioned infrastructure section.

Prerequisites

  • You have reviewed the OKD 4.x Tested Integrations page.

  • You have reviewed the infrastructure requirements detailed in the Requirements for a cluster with user-provisioned infrastructure section.

Procedure

  1. If you are using DHCP to provide the IP networking configuration to your cluster nodes, configure your DHCP service.

    1. Add persistent IP addresses for the nodes to your DHCP server configuration. In your configuration, match the MAC address of the relevant network interface to the intended IP address for each node.

    2. When you use DHCP to configure IP addressing for the cluster machines, the machines also obtain the DNS server information through DHCP. Define the persistent DNS server address that is used by the cluster nodes through your DHCP server configuration.

      If you are not using a DHCP service, you must provide the IP networking configuration and the address of the DNS server to the nodes at FCOS install time. These can be passed as boot arguments if you are installing from an ISO image. See the Installing FCOS and starting the OKD bootstrap process section for more information about static IP provisioning and advanced networking options.

    3. Define the hostnames of your cluster nodes in your DHCP server configuration. See the Setting the cluster node hostnames through DHCP section for details about hostname considerations.

      If you are not using a DHCP service, the cluster nodes obtain their hostname through a reverse DNS lookup.

  2. Ensure that your network infrastructure provides the required network connectivity between the cluster components. See the Networking requirements for user-provisioned infrastructure section for details about the requirements.

  3. Configure your firewall to enable the ports required for the OKD cluster components to communicate. See Networking requirements for user-provisioned infrastructure section for details about the ports that are required.

    By default, port 1936 is accessible for an OKD cluster, because each control plane node needs access to this port.

    Avoid using the Ingress load balancer to expose this port, because doing so might result in the exposure of sensitive information, such as statistics and metrics, related to Ingress Controllers.

  4. Setup the required DNS infrastructure for your cluster.

    1. Configure DNS name resolution for the Kubernetes API, the application wildcard, the bootstrap machine, the control plane machines, and the compute machines.

    2. Configure reverse DNS resolution for the Kubernetes API, the bootstrap machine, the control plane machines, and the compute machines.

      See the User-provisioned DNS requirements section for more information about the OKD DNS requirements.

  5. Validate your DNS configuration.

    1. From your installation node, run DNS lookups against the record names of the Kubernetes API, the wildcard routes, and the cluster nodes. Validate that the IP addresses in the responses correspond to the correct components.

    2. From your installation node, run reverse DNS lookups against the IP addresses of the load balancer and the cluster nodes. Validate that the record names in the responses correspond to the correct components.

      See the Validating DNS resolution for user-provisioned infrastructure section for detailed DNS validation steps.

  6. Provision the required API and application ingress load balancing infrastructure. See the Load balancing requirements for user-provisioned infrastructure section for more information about the requirements.

Some load balancing solutions require the DNS name resolution for the cluster nodes to be in place before the load balancing is initialized.

Validating DNS resolution for user-provisioned infrastructure

You can validate your DNS configuration before installing OKD on user-provisioned infrastructure.

The validation steps detailed in this section must succeed before you install your cluster.

Prerequisites

  • You have configured the required DNS records for your user-provisioned infrastructure.

Procedure

  1. From your installation node, run DNS lookups against the record names of the Kubernetes API, the wildcard routes, and the cluster nodes. Validate that the IP addresses contained in the responses correspond to the correct components.

    1. Perform a lookup against the Kubernetes API record name. Check that the result points to the IP address of the API load balancer:

      1. $ dig +noall +answer @<nameserver_ip> api.<cluster_name>.<base_domain> (1)
      1Replace <nameserver_ip> with the IP address of the nameserver, <cluster_name> with your cluster name, and <base_domain> with your base domain name.

      Example output

      1. api.ocp4.example.com. 604800 IN A 192.168.1.5
    2. Perform a lookup against the Kubernetes internal API record name. Check that the result points to the IP address of the API load balancer:

      1. $ dig +noall +answer @<nameserver_ip> api-int.<cluster_name>.<base_domain>

      Example output

      1. api-int.ocp4.example.com. 604800 IN A 192.168.1.5
    3. Test an example *.apps.<cluster_name>.<base_domain> DNS wildcard lookup. All of the application wildcard lookups must resolve to the IP address of the application ingress load balancer:

      1. $ dig +noall +answer @<nameserver_ip> random.apps.<cluster_name>.<base_domain>

      Example output

      1. random.apps.ocp4.example.com. 604800 IN A 192.168.1.5

      In the example outputs, the same load balancer is used for the Kubernetes API and application ingress traffic. In production scenarios, you can deploy the API and application ingress load balancers separately so that you can scale the load balancer infrastructure for each in isolation.

      You can replace random with another wildcard value. For example, you can query the route to the OKD console:

      1. $ dig +noall +answer @<nameserver_ip> console-openshift-console.apps.<cluster_name>.<base_domain>

      Example output

      1. console-openshift-console.apps.ocp4.example.com. 604800 IN A 192.168.1.5
    4. Run a lookup against the bootstrap DNS record name. Check that the result points to the IP address of the bootstrap node:

      1. $ dig +noall +answer @<nameserver_ip> bootstrap.<cluster_name>.<base_domain>

      Example output

      1. bootstrap.ocp4.example.com. 604800 IN A 192.168.1.96
    5. Use this method to perform lookups against the DNS record names for the control plane and compute nodes. Check that the results correspond to the IP addresses of each node.

  2. From your installation node, run reverse DNS lookups against the IP addresses of the load balancer and the cluster nodes. Validate that the record names contained in the responses correspond to the correct components.

    1. Perform a reverse lookup against the IP address of the API load balancer. Check that the response includes the record names for the Kubernetes API and the Kubernetes internal API:

      1. $ dig +noall +answer @<nameserver_ip> -x 192.168.1.5

      Example output

      1. 5.1.168.192.in-addr.arpa. 604800 IN PTR api-int.ocp4.example.com. (1)
      2. 5.1.168.192.in-addr.arpa. 604800 IN PTR api.ocp4.example.com. (2)
      1Provides the record name for the Kubernetes internal API.
      2Provides the record name for the Kubernetes API.

      A PTR record is not required for the OKD application wildcard. No validation step is needed for reverse DNS resolution against the IP address of the application ingress load balancer.

    2. Perform a reverse lookup against the IP address of the bootstrap node. Check that the result points to the DNS record name of the bootstrap node:

      1. $ dig +noall +answer @<nameserver_ip> -x 192.168.1.96

      Example output

      1. 96.1.168.192.in-addr.arpa. 604800 IN PTR bootstrap.ocp4.example.com.
    3. Use this method to perform reverse lookups against the IP addresses for the control plane and compute nodes. Check that the results correspond to the DNS record names of each node.

Generating a key pair for cluster node SSH access

During an OKD installation, you can provide an SSH public key to the installation program. The key is passed to the Fedora CoreOS (FCOS) nodes through their Ignition config files and is used to authenticate SSH access to the nodes. The key is added to the ~/.ssh/authorized_keys list for the core user on each node, which enables password-less authentication.

After the key is passed to the nodes, you can use the key pair to SSH in to the FCOS nodes as the user core. To access the nodes through SSH, the private key identity must be managed by SSH for your local user.

If you want to SSH in to your cluster nodes to perform installation debugging or disaster recovery, you must provide the SSH public key during the installation process. The ./openshift-install gather command also requires the SSH public key to be in place on the cluster nodes.

Do not skip this procedure in production environments, where disaster recovery and debugging is required.

You must use a local key, not one that you configured with platform-specific approaches such as AWS key pairs.

On clusters running Fedora CoreOS (FCOS), the SSH keys specified in the Ignition config files are written to the /home/core/.ssh/authorized_keys.d/core file. However, the Machine Config Operator manages SSH keys in the /home/core/.ssh/authorized_keys file and configures sshd to ignore the /home/core/.ssh/authorized_keys.d/core file. As a result, newly provisioned OKD nodes are not accessible using SSH until the Machine Config Operator reconciles the machine configs with the authorized_keys file. After you can access the nodes using SSH, you can delete the /home/core/.ssh/authorized_keys.d/core file.

Procedure

  1. If you do not have an existing SSH key pair on your local machine to use for authentication onto your cluster nodes, create one. For example, on a computer that uses a Linux operating system, run the following command:

    1. $ ssh-keygen -t ed25519 -N '' -f <path>/<file_name> (1)
    1Specify the path and file name, such as ~/.ssh/id_ed25519, of the new SSH key. If you have an existing key pair, ensure your public key is in the your ~/.ssh directory.

    If you plan to install an OKD cluster that uses the Fedora cryptographic libraries that have been submitted to NIST for FIPS 140-2/140-3 Validation on only the x86_64, ppc64le, and s390x architectures, do not create a key that uses the ed25519 algorithm. Instead, create a key that uses the rsa or ecdsa algorithm.

  2. View the public SSH key:

    1. $ cat <path>/<file_name>.pub

    For example, run the following to view the ~/.ssh/id_ed25519.pub public key:

    1. $ cat ~/.ssh/id_ed25519.pub
  3. Add the SSH private key identity to the SSH agent for your local user, if it has not already been added. SSH agent management of the key is required for password-less SSH authentication onto your cluster nodes, or if you want to use the ./openshift-install gather command.

    On some distributions, default SSH private key identities such as ~/.ssh/id_rsa and ~/.ssh/id_dsa are managed automatically.

    1. If the ssh-agent process is not already running for your local user, start it as a background task:

      1. $ eval "$(ssh-agent -s)"

      Example output

      1. Agent pid 31874

      If your cluster is in FIPS mode, only use FIPS-compliant algorithms to generate the SSH key. The key must be either RSA or ECDSA.

  4. Add your SSH private key to the ssh-agent:

    1. $ ssh-add <path>/<file_name> (1)
    1Specify the path and file name for your SSH private key, such as ~/.ssh/id_ed25519

    Example output

    1. Identity added: /home/<you>/<path>/<file_name> (<computer_name>)

Next steps

  • When you install OKD, provide the SSH public key to the installation program. If you install a cluster on infrastructure that you provision, you must provide the key to the installation program.

VMware vSphere region and zone enablement

You can deploy an OKD cluster to multiple vSphere datacenters that run in a single VMware vCenter. Each datacenter can run multiple clusters. This configuration reduces the risk of a hardware failure or network outage that can cause your cluster to fail.

The VMware vSphere region and zone enablement feature requires the vSphere Container Storage Interface (CSI) driver as the default storage driver in the cluster. As a result, the feature only available on a newly installed cluster.

A cluster that was upgraded from a previous release defaults to using the in-tree vSphere driver, so you must enable CSI automatic migration for the cluster. You can then configure multiple regions and zones for the upgraded cluster.

The default installation configuration deploys a cluster to a single vSphere datacenter. If you want to deploy a cluster to multiple vSphere datacenters, you must create an installation configuration file that enables the region and zone feature.

The default install-config.yaml file includes vcenters and failureDomains fields, where you can specify multiple vSphere datacenters and clusters for your OKD cluster. You can leave these fields blank if you want to install an OKD cluster in a vSphere environment that consists of single datacenter.

The following list describes terms associated with defining zones and regions for your cluster:

  • Failure domain: Establishes the relationships between a region and zone. You define a failure domain by using vCenter objects, such as a datastore object. A failure domain defines the vCenter location for OKD cluster nodes.

  • Region: Specifies a vCenter datacenter. You define a region by using a tag from the openshift-region tag category.

  • Zone: Specifies a vCenter cluster. You define a zone by using a tag from the openshift-zone tag category.

If you plan on specifying more than one failure domain in your install-config.yaml file, you must create tag categories, zone tags, and region tags in advance of creating the configuration file.

You must create a vCenter tag for each vCenter datacenter, which represents a region. Additionally, you must create a vCenter tag for each cluster than runs in a datacenter, which represents a zone. After you create the tags, you must attach each tag to their respective datacenters and clusters.

The following table outlines an example of the relationship among regions, zones, and tags for a configuration with multiple vSphere datacenters running in a single VMware vCenter.

Datacenter (region)Cluster (zone)Tags

us-east

us-east-1

us-east-1a

us-east-1b

us-east-2

us-east-2a

us-east-2b

us-west

us-west-1

us-west-1a

us-west-1b

us-west-2

us-west-2a

us-west-2b

Additional resources

Manually creating the installation configuration file

For user-provisioned installations of OKD, you manually generate your installation configuration file.

The Cluster Cloud Controller Manager Operator performs a connectivity check on a provided hostname or IP address. Ensure that you specify a hostname or an IP address to a reachable vCenter server. If you provide metadata to a non-existent vCenter server, installation of the cluster fails at the bootstrap stage.

Prerequisites

  • You have an SSH public key on your local machine to provide to the installation program. The key will be used for SSH authentication onto your cluster nodes for debugging and disaster recovery.

  • You have obtained the OKD installation program and the pull secret for your cluster.

  • Obtain the imageContentSources section from the output of the command to mirror the repository.

  • Obtain the contents of the certificate for your mirror registry.

Procedure

  1. Create an installation directory to store your required installation assets in:

    1. $ mkdir <installation_directory>

    You must create a directory. Some installation assets, like bootstrap X.509 certificates have short expiration intervals, so you must not reuse an installation directory. If you want to reuse individual files from another cluster installation, you can copy them into your directory. However, the file names for the installation assets might change between releases. Use caution when copying installation files from an earlier OKD version.

  2. Customize the sample install-config.yaml file template that is provided and save it in the <installation_directory>.

    You must name this configuration file install-config.yaml.

    • Unless you use a registry that FCOS trusts by default, such as docker.io, you must provide the contents of the certificate for your mirror repository in the additionalTrustBundle section. In most cases, you must provide the certificate for your mirror.

    • You must include the imageContentSources section from the output of the command to mirror the repository.

      • The ImageContentSourcePolicy file is generated as an output of oc mirror after the mirroring process is finished.

      • The oc mirror command generates an ImageContentSourcePolicy file which contains the YAML needed to define ImageContentSourcePolicy. Copy the text from this file and paste it into your install-config.yaml file.

      • You must run the ‘oc mirror’ command twice. The first time you run the oc mirror command, you get a full ImageContentSourcePolicy file. The second time you run the oc mirror command, you only get the difference between the first and second run. Because of this behavior, you must always keep a backup of these files in case you need to merge them into one complete ImageContentSourcePolicy file. Keeping a backup of these two output files ensures that you have a complete ImageContentSourcePolicy file.

    For some platform types, you can alternatively run ./openshift-install create install-config —dir <installation_directory> to generate an install-config.yaml file. You can provide details about your cluster configuration at the prompts.

  3. Back up the install-config.yaml file so that you can use it to install multiple clusters.

    The install-config.yaml file is consumed during the next step of the installation process. You must back it up now.

Additional resources

Sample install-config.yaml file for VMware vSphere

You can customize the install-config.yaml file to specify more details about your OKD cluster’s platform or modify the values of the required parameters.

  1. additionalTrustBundlePolicy: Proxyonly
  2. apiVersion: v1
  3. baseDomain: example.com (1)
  4. compute: (2)
  5. - architecture: amd64
  6. hyperthreading: Enabled (3)
  7. name: <worker_node>
  8. platform: {}
  9. replicas: 0 (4)
  10. controlPlane: (2)
  11. architecture: amd64
  12. hyperthreading: Enabled (3)
  13. name: <parent_node>
  14. platform: {}
  15. replicas: 3 (5)
  16. metadata:
  17. creationTimestamp: null
  18. name: test (6)
  19. networking:
  20. ---
  21. platform:
  22. vsphere:
  23. failureDomains: (7)
  24. - name: <failure_domain_name>
  25. region: <default_region_name>
  26. server: <fully_qualified_domain_name>
  27. topology:
  28. computeCluster: "/<datacenter>/host/<cluster>"
  29. datacenter: <datacenter> (8)
  30. datastore: "/<datacenter>/datastore/<datastore>" (9)
  31. networks:
  32. - <VM_Network_name>
  33. resourcePool: "/<datacenter>/host/<cluster>/Resources/<resourcePool>" (10)
  34. folder: "/<datacenter_name>/vm/<folder_name>/<subfolder_name>" (11)
  35. zone: <default_zone_name>
  36. vcenters:
  37. - datacenters:
  38. - <datacenter>
  39. password: <password> (12)
  40. port: 443
  41. server: <fully_qualified_domain_name> (13)
  42. user: administrator@vsphere.local
  43. diskType: thin (14)
  44. pullSecret: '{"auths":{"<local_registry>": {"auth": "<credentials>","email": "you@example.com"}}}' (15)
  45. sshKey: 'ssh-ed25519 AAAA...' (16)
  46. additionalTrustBundle: | (17)
  47. -----BEGIN CERTIFICATE-----
  48. ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
  49. -----END CERTIFICATE-----
  50. imageContentSources: (18)
  51. - mirrors:
  52. - <local_registry>/<local_repository_name>/release
  53. source: quay.io/openshift-release-dev/ocp-release
  54. - mirrors:
  55. - <local_registry>/<local_repository_name>/release
  56. source: quay.io/openshift-release-dev/ocp-v4.0-art-dev
1The base domain of the cluster. All DNS records must be sub-domains of this base and include the cluster name.
2The controlPlane section is a single mapping, but the compute section is a sequence of mappings. To meet the requirements of the different data structures, the first line of the compute section must begin with a hyphen, -, and the first line of the controlPlane section must not. Both sections define a single machine pool, so only one control plane is used. OKD does not support defining multiple compute pools.
3Whether to enable or disable simultaneous multithreading, or hyperthreading. By default, simultaneous multithreading is enabled to increase the performance of your machines’ cores. You can disable it by setting the parameter value to Disabled. If you disable simultaneous multithreading in some cluster machines, you must disable it in all cluster machines.

If you disable simultaneous multithreading, ensure that your capacity planning accounts for the dramatically decreased machine performance. Your machines must use at least 8 CPUs and 32 GB of RAM if you disable simultaneous multithreading.

4You must set the value of the replicas parameter to 0. This parameter controls the number of workers that the cluster creates and manages for you, which are functions that the cluster does not perform when you use user-provisioned infrastructure. You must manually deploy worker machines for the cluster to use before you finish installing OKD.
5The number of control plane machines that you add to the cluster. Because the cluster uses this values as the number of etcd endpoints in the cluster, the value must match the number of control plane machines that you deploy.
6The cluster name that you specified in your DNS records.
7Establishes the relationships between a region and zone. You define a failure domain by using vCenter objects, such as a datastore object. A failure domain defines the vCenter location for OKD cluster nodes.
8The vSphere datacenter.
9The path to the vSphere datastore that holds virtual machine files, templates, and ISO images.

You can specify the path of any datastore that exists in a datastore cluster. By default, Storage vMotion is automatically enabled for a datastore cluster. Red Hat does not support Storage vMotion, so you must disable Storage vMotion to avoid data loss issues for your OKD cluster.

If you must specify VMs across multiple datastores, use a datastore object to specify a failure domain in your cluster’s install-config.yaml configuration file. For more information, see “VMware vSphere region and zone enablement”.

10Optional: For installer-provisioned infrastructure, the absolute path of an existing resource pool where the installation program creates the virtual machines, for example, /<datacenter_name>/host/<cluster_name>/Resources/<resource_pool_name>/<optional_nested_resource_pool_name>. If you do not specify a value, resources are installed in the root of the cluster /example_datacenter/host/example_cluster/Resources.
11Optional: For installer-provisioned infrastructure, the absolute path of an existing folder where the installation program creates the virtual machines, for example, /<datacenter_name>/vm/<folder_name>/<subfolder_name>. If you do not provide this value, the installation program creates a top-level folder in the datacenter virtual machine folder that is named with the infrastructure ID. If you are providing the infrastructure for the cluster and you do not want to use the default StorageClass object, named thin, you can omit the folder parameter from the install-config.yaml file.
12The password associated with the vSphere user.
13The fully-qualified hostname or IP address of the vCenter server.

The Cluster Cloud Controller Manager Operator performs a connectivity check on a provided hostname or IP address. Ensure that you specify a hostname or an IP address to a reachable vCenter server. If you provide metadata to a non-existent vCenter server, installation of the cluster fails at the bootstrap stage.

14The vSphere disk provisioning method.
15For <local_registry>, specify the registry domain name, and optionally the port, that your mirror registry uses to serve content. For example registry.example.com or registry.example.com:5000. For <credentials>, specify the base64-encoded user name and password for your mirror registry.
16The public portion of the default SSH key for the core user in Fedora CoreOS (FCOS).

For production OKD clusters on which you want to perform installation debugging or disaster recovery, specify an SSH key that your ssh-agent process uses.

17Provide the contents of the certificate file that you used for your mirror registry.
18Provide the imageContentSources section from the output of the command to mirror the repository.

Configuring the cluster-wide proxy during installation

Production environments can deny direct access to the internet and instead have an HTTP or HTTPS proxy available. You can configure a new OKD cluster to use a proxy by configuring the proxy settings in the install-config.yaml file.

Prerequisites

  • You have an existing install-config.yaml file.

  • You reviewed the sites that your cluster requires access to and determined whether any of them need to bypass the proxy. By default, all cluster egress traffic is proxied, including calls to hosting cloud provider APIs. You added sites to the Proxy object’s spec.noProxy field to bypass the proxy if necessary.

    The Proxy object status.noProxy field is populated with the values of the networking.machineNetwork[].cidr, networking.clusterNetwork[].cidr, and networking.serviceNetwork[] fields from your installation configuration.

    For installations on Amazon Web Services (AWS), Google Cloud Platform (GCP), Microsoft Azure, and OpenStack, the Proxy object status.noProxy field is also populated with the instance metadata endpoint (169.254.169.254).

Procedure

  1. Edit your install-config.yaml file and add the proxy settings. For example:

    1. apiVersion: v1
    2. baseDomain: my.domain.com
    3. proxy:
    4. httpProxy: http://<username>:<pswd>@<ip>:<port> (1)
    5. httpsProxy: https://<username>:<pswd>@<ip>:<port> (2)
    6. noProxy: example.com (3)
    7. additionalTrustBundle: | (4)
    8. -----BEGIN CERTIFICATE-----
    9. <MY_TRUSTED_CA_CERT>
    10. -----END CERTIFICATE-----
    11. additionalTrustBundlePolicy: <policy_to_add_additionalTrustBundle> (5)
    1A proxy URL to use for creating HTTP connections outside the cluster. The URL scheme must be http.
    2A proxy URL to use for creating HTTPS connections outside the cluster.
    3A comma-separated list of destination domain names, IP addresses, or other network CIDRs to exclude from proxying. Preface a domain with . to match subdomains only. For example, .y.com matches x.y.com, but not y.com. Use * to bypass the proxy for all destinations. You must include vCenter’s IP address and the IP range that you use for its machines.
    4If provided, the installation program generates a config map that is named user-ca-bundle in the openshift-config namespace that contains one or more additional CA certificates that are required for proxying HTTPS connections. The Cluster Network Operator then creates a trusted-ca-bundle config map that merges these contents with the Fedora CoreOS (FCOS) trust bundle, and this config map is referenced in the trustedCA field of the Proxy object. The additionalTrustBundle field is required unless the proxy’s identity certificate is signed by an authority from the FCOS trust bundle.
    5Optional: The policy to determine the configuration of the Proxy object to reference the user-ca-bundle config map in the trustedCA field. The allowed values are Proxyonly and Always. Use Proxyonly to reference the user-ca-bundle config map only when http/https proxy is configured. Use Always to always reference the user-ca-bundle config map. The default value is Proxyonly.

    The installation program does not support the proxy readinessEndpoints field.

    If the installer times out, restart and then complete the deployment by using the wait-for command of the installer. For example:

    1. $ ./openshift-install wait-for install-complete log-level debug
  2. Save the file and reference it when installing OKD.

The installation program creates a cluster-wide proxy that is named cluster that uses the proxy settings in the provided install-config.yaml file. If no proxy settings are provided, a cluster Proxy object is still created, but it will have a nil spec.

Only the Proxy object named cluster is supported, and no additional proxies can be created.

Configuring regions and zones for a VMware vCenter

You can modify the default installation configuration file, so that you can deploy an OKD cluster to multiple vSphere datacenters that run in a single VMware vCenter.

The default install-config.yaml file configuration from the previous release of OKD is deprecated. You can continue to use the deprecated default configuration, but the openshift-installer will prompt you with a warning message that indicates the use of deprecated fields in the configuration file.

The example uses the govc command. The govc command is an open source command available from VMware; it is not available from Red Hat. The Red Hat support team does not maintain the govc command. Instructions for downloading and installing govc are found on the VMware documentation website

Prerequisites

  • You have an existing install-config.yaml installation configuration file.

    You must specify at least one failure domain for your OKD cluster, so that you can provision datacenter objects for your VMware vCenter server. Consider specifying multiple failure domains if you need to provision virtual machine nodes in different datacenters, clusters, datastores, and other components.

Procedure

  1. Enter the following govc command-line tool commands to create the openshift-region and openshift-zone vCenter tag categories:

    If you specify different names for the openshift-region and openshift-zone vCenter tag categories, the installation of the OKD cluster fails.

    1. $ govc tags.category.create -d "OpenShift region" openshift-region
    1. $ govc tags.category.create -d "OpenShift zone" openshift-zone
  2. To create a region tag for each region vSphere datacenter where you want to deploy your cluster, enter the following command in your terminal:

    1. $ govc tags.create -c <region_tag_category> <region_tag>
  3. To create a zone tag for each vSphere cluster where you want to deploy your cluster, enter the following command:

    1. $ govc tags.create -c <zone_tag_category> <zone_tag>
  4. Attach region tags to each vCenter datacenter object by entering the following command:

    1. $ govc tags.attach -c <region_tag_category> <region_tag_1> /<datacenter_1>
  5. Attach the zone tags to each vCenter datacenter object by entering the following command:

    1. $ govc tags.attach -c <zone_tag_category> <zone_tag_1> /<datacenter_1>/host/vcs-mdcnc-workload-1
  6. Change to the directory that contains the installation program and initialize the cluster deployment according to your chosen installation requirements.

Sample install-config.yaml file with multiple datacenters defined in a vSphere center

  1. ---
  2. compute:
  3. ---
  4. vsphere:
  5. zones:
  6. - "<machine_pool_zone_1>"
  7. - "<machine_pool_zone_2>"
  8. ---
  9. controlPlane:
  10. ---
  11. vsphere:
  12. zones:
  13. - "<machine_pool_zone_1>"
  14. - "<machine_pool_zone_2>"
  15. ---
  16. platform:
  17. vsphere:
  18. vcenters:
  19. ---
  20. datacenters:
  21. - <datacenter1_name>
  22. - <datacenter2_name>
  23. failureDomains:
  24. - name: <machine_pool_zone_1>
  25. region: <region_tag_1>
  26. zone: <zone_tag_1>
  27. server: <fully_qualified_domain_name>
  28. topology:
  29. datacenter: <datacenter1>
  30. computeCluster: "/<datacenter1>/host/<cluster1>"
  31. networks:
  32. - <VM_Network1_name>
  33. datastore: "/<datacenter1>/datastore/<datastore1>"
  34. resourcePool: "/<datacenter1>/host/<cluster1>/Resources/<resourcePool1>"
  35. folder: "/<datacenter1>/vm/<folder1>"
  36. - name: <machine_pool_zone_2>
  37. region: <region_tag_2>
  38. zone: <zone_tag_2>
  39. server: <fully_qualified_domain_name>
  40. topology:
  41. datacenter: <datacenter2>
  42. computeCluster: "/<datacenter2>/host/<cluster2>"
  43. networks:
  44. - <VM_Network2_name>
  45. datastore: "/<datacenter2>/datastore/<datastore2>"
  46. resourcePool: "/<datacenter2>/host/<cluster2>/Resources/<resourcePool2>"
  47. folder: "/<datacenter2>/vm/<folder2>"
  48. ---

Creating the Kubernetes manifest and Ignition config files

Because you must modify some cluster definition files and manually start the cluster machines, you must generate the Kubernetes manifest and Ignition config files that the cluster needs to configure the machines.

The installation configuration file transforms into the Kubernetes manifests. The manifests wrap into the Ignition configuration files, which are later used to configure the cluster machines.

  • The Ignition config files that the OKD installation program generates contain certificates that expire after 24 hours, which are then renewed at that time. If the cluster is shut down before renewing the certificates and the cluster is later restarted after the 24 hours have elapsed, the cluster automatically recovers the expired certificates. The exception is that you must manually approve the pending node-bootstrapper certificate signing requests (CSRs) to recover kubelet certificates. See the documentation for Recovering from expired control plane certificates for more information.

  • It is recommended that you use Ignition config files within 12 hours after they are generated because the 24-hour certificate rotates from 16 to 22 hours after the cluster is installed. By using the Ignition config files within 12 hours, you can avoid installation failure if the certificate update runs during installation.

Prerequisites

  • You obtained the OKD installation program. For a restricted network installation, these files are on your mirror host.

  • You created the install-config.yaml installation configuration file.

Procedure

  1. Change to the directory that contains the OKD installation program and generate the Kubernetes manifests for the cluster:

    1. $ ./openshift-install create manifests --dir <installation_directory> (1)
    1For <installation_directory>, specify the installation directory that contains the install-config.yaml file you created.
  2. Remove the Kubernetes manifest files that define the control plane machines, compute machine sets, and control plane machine sets:

    1. $ rm -f openshift/99_openshift-cluster-api_master-machines-*.yaml openshift/99_openshift-cluster-api_worker-machineset-*.yaml openshift/99_openshift-machine-api_master-control-plane-machine-set.yaml

    Because you create and manage these resources yourself, you do not have to initialize them.

    • You can preserve the compute machine set files to create compute machines by using the machine API, but you must update references to them to match your environment.
  3. Check that the mastersSchedulable parameter in the <installation_directory>/manifests/cluster-scheduler-02-config.yml Kubernetes manifest file is set to false. This setting prevents pods from being scheduled on the control plane machines:

    1. Open the <installation_directory>/manifests/cluster-scheduler-02-config.yml file.

    2. Locate the mastersSchedulable parameter and ensure that it is set to false.

    3. Save and exit the file.

  4. To create the Ignition configuration files, run the following command from the directory that contains the installation program:

    1. $ ./openshift-install create ignition-configs --dir <installation_directory> (1)
    1For <installation_directory>, specify the same installation directory.

    Ignition config files are created for the bootstrap, control plane, and compute nodes in the installation directory. The kubeadmin-password and kubeconfig files are created in the ./<installation_directory>/auth directory:

    1. .
    2. ├── auth
    3. ├── kubeadmin-password
    4. └── kubeconfig
    5. ├── bootstrap.ign
    6. ├── master.ign
    7. ├── metadata.json
    8. └── worker.ign

Configuring chrony time service

You must set the time server and related settings used by the chrony time service (chronyd) by modifying the contents of the chrony.conf file and passing those contents to your nodes as a machine config.

Procedure

  1. Create a Butane config including the contents of the chrony.conf file. For example, to configure chrony on worker nodes, create a 99-worker-chrony.bu file.

    See “Creating machine configs with Butane” for information about Butane.

    1. variant: openshift
    2. version: 4.14.0
    3. metadata:
    4. name: 99-worker-chrony (1)
    5. labels:
    6. machineconfiguration.openshift.io/role: worker (1)
    7. storage:
    8. files:
    9. - path: /etc/chrony.conf
    10. mode: 0644 (2)
    11. overwrite: true
    12. contents:
    13. inline: |
    14. pool 0.rhel.pool.ntp.org iburst (3)
    15. driftfile /var/lib/chrony/drift
    16. makestep 1.0 3
    17. rtcsync
    18. logdir /var/log/chrony
    1On control plane nodes, substitute master for worker in both of these locations.
    2Specify an octal value mode for the mode field in the machine config file. After creating the file and applying the changes, the mode is converted to a decimal value. You can check the YAML file with the command oc get mc <mc-name> -o yaml.
    3Specify any valid, reachable time source, such as the one provided by your DHCP server.
  2. Use Butane to generate a MachineConfig object file, 99-worker-chrony.yaml, containing the configuration to be delivered to the nodes:

    1. $ butane 99-worker-chrony.bu -o 99-worker-chrony.yaml
  3. Apply the configurations in one of two ways:

    • If the cluster is not running yet, after you generate manifest files, add the MachineConfig object file to the <installation_directory>/openshift directory, and then continue to create the cluster.

    • If the cluster is already running, apply the file:

      1. $ oc apply -f ./99-worker-chrony.yaml

Extracting the infrastructure name

The Ignition config files contain a unique cluster identifier that you can use to uniquely identify your cluster in VMware vSphere. If you plan to use the cluster identifier as the name of your virtual machine folder, you must extract it.

Prerequisites

  • You obtained the OKD installation program and the pull secret for your cluster.

  • You generated the Ignition config files for your cluster.

  • You installed the jq package.

Procedure

  • To extract and view the infrastructure name from the Ignition config file metadata, run the following command:

    1. $ jq -r .infraID <installation_directory>/metadata.json (1)
    1For <installation_directory>, specify the path to the directory that you stored the installation files in.

    Example output

    1. openshift-vw9j6 (1)
    1The output of this command is your cluster name and a random string.

Installing FCOS and starting the OKD bootstrap process

To install OKD on user-provisioned infrastructure on VMware vSphere, you must install Fedora CoreOS (FCOS) on vSphere hosts. When you install FCOS, you must provide the Ignition config file that was generated by the OKD installation program for the type of machine you are installing. If you have configured suitable networking, DNS, and load balancing infrastructure, the OKD bootstrap process begins automatically after the FCOS machines have rebooted.

Prerequisites

  • You have obtained the Ignition config files for your cluster.

  • You have access to an HTTP server that you can access from your computer and that the machines that you create can access.

  • You have created a vSphere cluster.

Procedure

  1. Upload the bootstrap Ignition config file, which is named <installation_directory>/bootstrap.ign, that the installation program created to your HTTP server. Note the URL of this file.

  2. Save the following secondary Ignition config file for your bootstrap node to your computer as <installation_directory>/merge-bootstrap.ign:

    1. {
    2. "ignition": {
    3. "config": {
    4. "merge": [
    5. {
    6. "source": "<bootstrap_ignition_config_url>", (1)
    7. "verification": {}
    8. }
    9. ]
    10. },
    11. "timeouts": {},
    12. "version": "3.2.0"
    13. },
    14. "networkd": {},
    15. "passwd": {},
    16. "storage": {},
    17. "systemd": {}
    18. }
    1Specify the URL of the bootstrap Ignition config file that you hosted.

    When you create the virtual machine (VM) for the bootstrap machine, you use this Ignition config file.

  3. Locate the following Ignition config files that the installation program created:

    • <installation_directory>/master.ign

    • <installation_directory>/worker.ign

    • <installation_directory>/merge-bootstrap.ign

  4. Convert the Ignition config files to Base64 encoding. Later in this procedure, you must add these files to the extra configuration parameter guestinfo.ignition.config.data in your VM.

    For example, if you use a Linux operating system, you can use the base64 command to encode the files.

    1. $ base64 -w0 <installation_directory>/master.ign > <installation_directory>/master.64
    1. $ base64 -w0 <installation_directory>/worker.ign > <installation_directory>/worker.64
    1. $ base64 -w0 <installation_directory>/merge-bootstrap.ign > <installation_directory>/merge-bootstrap.64

    If you plan to add more compute machines to your cluster after you finish installation, do not delete these files.

  5. Obtain the FCOS images from the FCOS Downloads page

  6. In the vSphere Client, create a folder in your datacenter to store your VMs.

    1. Click the VMs and Templates view.

    2. Right-click the name of your datacenter.

    3. Click New FolderNew VM and Template Folder.

    4. In the window that is displayed, enter the folder name. If you did not specify an existing folder in the install-config.yaml file, then create a folder with the same name as the infrastructure ID. You use this folder name so vCenter dynamically provisions storage in the appropriate location for its Workspace configuration.

  7. In the vSphere Client, create a template for the OVA image and then clone the template as needed.

    In the following steps, you create a template and then clone the template for all of your cluster machines. You then provide the location for the Ignition config file for that cloned machine type when you provision the VMs.

    1. From the Hosts and Clusters tab, right-click your cluster name and select Deploy OVF Template.

    2. On the Select an OVF tab, specify the name of the FCOS OVA file that you downloaded.

    3. On the Select a name and folder tab, set a Virtual machine name for your template, such as Template-FCOS. Click the name of your vSphere cluster and select the folder you created in the previous step.

    4. On the Select a compute resource tab, click the name of your vSphere cluster.

    5. On the Select storage tab, configure the storage options for your VM.

      • Select Thin Provision or Thick Provision, based on your storage preferences.

      • Select the datastore that you specified in your install-config.yaml file.

      • If you want to encrypt your virtual machines, select Encrypt this virtual machine. See the section titled “Requirements for encrypting virtual machines” for more information.

    6. On the Select network tab, specify the network that you configured for the cluster, if available.

    7. When creating the OVF template, do not specify values on the Customize template tab or configure the template any further.

      Do not start the original VM template. The VM template must remain off and must be cloned for new FCOS machines. Starting the VM template configures the VM template as a VM on the platform, which prevents it from being used as a template that compute machine sets can apply configurations to.

  8. Optional: Update the configured virtual hardware version in the VM template, if necessary. Follow Upgrading a virtual machine to the latest hardware version in the VMware documentation for more information.

    It is recommended that you update the hardware version of the VM template to version 15 before creating VMs from it, if necessary. Using hardware version 13 for your cluster nodes running on vSphere is now deprecated. If your imported template defaults to hardware version 13, you must ensure that your ESXi host is on 6.7U3 or later before upgrading the VM template to hardware version 15. If your vSphere version is less than 6.7U3, you can skip this upgrade step; however, a future version of OKD is scheduled to remove support for hardware version 13 and vSphere versions less than 6.7U3.

  9. After the template deploys, deploy a VM for a machine in the cluster.

    1. Right-click the template name and click CloneClone to Virtual Machine.

    2. On the Select a name and folder tab, specify a name for the VM. You might include the machine type in the name, such as control-plane-0 or compute-1.

      Ensure that all virtual machine names across a vSphere installation are unique.

    3. On the Select a name and folder tab, select the name of the folder that you created for the cluster.

    4. On the Select a compute resource tab, select the name of a host in your datacenter.

    5. On the Select clone options tab, select Customize this virtual machine’s hardware.

    6. On the Customize hardware tab, click Advanced Parameters.

      The following configuration suggestions are for example purposes only. As a cluster administrator, you must configure resources according to the resource demands placed on your cluster. To best manage cluster resources, consider creating a resource pool from the cluster’s root resource pool.

      • Optional: Override default DHCP networking in vSphere. To enable static IP networking:

        • Set your static IP configuration:

          Example command

          1. $ export IPCFG="ip=<ip>::<gateway>:<netmask>:<hostname>:<iface>:none nameserver=srv1 [nameserver=srv2 [nameserver=srv3 [...]]]"

          Example command

          1. $ export IPCFG="ip=192.168.100.101::192.168.100.254:255.255.255.0:::none nameserver=8.8.8.8"
        • Set the guestinfo.afterburn.initrd.network-kargs property before you boot a VM from an OVA in vSphere:

          Example command

          1. $ govc vm.change -vm "<vm_name>" -e "guestinfo.afterburn.initrd.network-kargs=${IPCFG}"
      • Add the following configuration parameter names and values by specifying data in the Attribute and Values fields. Ensure that you select the Add button for each parameter that you create.

        • guestinfo.ignition.config.data: Locate the base-64 encoded files that you created previously in this procedure, and paste the contents of the base64-encoded Ignition config file for this machine type.

        • guestinfo.ignition.config.data.encoding: Specify base64.

        • disk.EnableUUID: Specify TRUE.

        • stealclock.enable: If this parameter was not defined, add it and specify TRUE.

        • Create a child resource pool from the cluster’s root resource pool. Perform resource allocation in this child resource pool.

  1. 7. In the **Virtual Hardware** panel of the **Customize hardware** tab, modify the specified values as required. Ensure that the amount of RAM, CPU, and disk storage meets the minimum requirements for the machine type.
  2. 8. Complete the remaining configuration steps. On clicking the **Finish** button, you have completed the cloning operation.
  3. 9. From the **Virtual Machines** tab, right-click on your VM and then select **Power** **Power On**.
  4. 10. Check the console output to verify that Ignition ran.
  5. Example command
  6. ```
  7. Ignition: ran on 2022/03/14 14:48:33 UTC (this boot)
  8. Ignition: user-provided config was applied
  9. ```

Next steps

  • Create the rest of the machines for your cluster by following the preceding steps for each machine.

    You must create the bootstrap and control plane machines at this time. Because some pods are deployed on compute machines by default, also create at least two compute machines before you install the cluster.

Adding more compute machines to a cluster in vSphere

You can add more compute machines to a user-provisioned OKD cluster on VMware vSphere.

After your vSphere template deploys in your OKD cluster, you can deploy a virtual machine (VM) for a machine in that cluster.

Prerequisites

  • Obtain the base64-encoded Ignition file for your compute machines.

  • You have access to the vSphere template that you created for your cluster.

Procedure

  1. Right-click the template’s name and click CloneClone to Virtual Machine.

  2. On the Select a name and folder tab, specify a name for the VM. You might include the machine type in the name, such as compute-1.

    Ensure that all virtual machine names across a vSphere installation are unique.

  3. On the Select a name and folder tab, select the name of the folder that you created for the cluster.

  4. On the Select a compute resource tab, select the name of a host in your datacenter.

  5. On the Select storage tab, select storage for your configuration and disk files.

  6. On the Select clone options tab, select Customize this virtual machine’s hardware.

  7. On the Customize hardware tab, click Advanced Parameters.

    • Add the following configuration parameter names and values by specifying data in the Attribute and Values fields. Ensure that you select the Add button for each parameter that you create.

      • guestinfo.ignition.config.data: Paste the contents of the base64-encoded compute Ignition config file for this machine type.

      • guestinfo.ignition.config.data.encoding: Specify base64.

      • disk.EnableUUID: Specify TRUE.

  1. In the Virtual Hardware panel of the Customize hardware tab, modify the specified values as required. Ensure that the amount of RAM, CPU, and disk storage meets the minimum requirements for the machine type. If many networks exist, select Add New Device > Network Adapter, and then enter your network information in the fields provided by the New Network menu item.

  2. Complete the remaining configuration steps. On clicking the Finish button, you have completed the cloning operation.

  3. From the Virtual Machines tab, right-click on your VM and then select PowerPower On.

Next steps

  • Continue to create more compute machines for your cluster.

Disk partitioning

In most cases, data partitions are originally created by installing FCOS, rather than by installing another operating system. In such cases, the OKD installer should be allowed to configure your disk partitions.

However, there are two cases where you might want to intervene to override the default partitioning when installing an OKD node:

  • Create separate partitions: For greenfield installations on an empty disk, you might want to add separate storage to a partition. This is officially supported for making /var or a subdirectory of /var, such as /var/lib/etcd, a separate partition, but not both.

    For disk sizes larger than 100GB, and especially disk sizes larger than 1TB, create a separate /var partition. See “Creating a separate /var partition” and this Red Hat Knowledgebase article for more information.

    Kubernetes supports only two file system partitions. If you add more than one partition to the original configuration, Kubernetes cannot monitor all of them.

  • Retain existing partitions: For a brownfield installation where you are reinstalling OKD on an existing node and want to retain data partitions installed from your previous operating system, there are both boot arguments and options to coreos-installer that allow you to retain existing data partitions.

Creating a separate /var partition

In general, disk partitioning for OKD should be left to the installer. However, there are cases where you might want to create separate partitions in a part of the filesystem that you expect to grow.

OKD supports the addition of a single partition to attach storage to either the /var partition or a subdirectory of /var. For example:

  • /var/lib/containers: Holds container-related content that can grow as more images and containers are added to a system.

  • /var/lib/etcd: Holds data that you might want to keep separate for purposes such as performance optimization of etcd storage.

  • /var: Holds data that you might want to keep separate for purposes such as auditing.

    For disk sizes larger than 100GB, and especially larger than 1TB, create a separate /var partition.

Storing the contents of a /var directory separately makes it easier to grow storage for those areas as needed and reinstall OKD at a later date and keep that data intact. With this method, you will not have to pull all your containers again, nor will you have to copy massive log files when you update systems.

Because /var must be in place before a fresh installation of Fedora CoreOS (FCOS), the following procedure sets up the separate /var partition by creating a machine config manifest that is inserted during the openshift-install preparation phases of an OKD installation.

Procedure

  1. Create a directory to hold the OKD installation files:

    1. $ mkdir $HOME/clusterconfig
  2. Run openshift-install to create a set of files in the manifest and openshift subdirectories. Answer the system questions as you are prompted:

    1. $ openshift-install create manifests --dir $HOME/clusterconfig
    2. ? SSH Public Key ...
    3. $ ls $HOME/clusterconfig/openshift/
    4. 99_kubeadmin-password-secret.yaml
    5. 99_openshift-cluster-api_master-machines-0.yaml
    6. 99_openshift-cluster-api_master-machines-1.yaml
    7. 99_openshift-cluster-api_master-machines-2.yaml
    8. ...
  3. Create a Butane config that configures the additional partition. For example, name the file $HOME/clusterconfig/98-var-partition.bu, change the disk device name to the name of the storage device on the worker systems, and set the storage size as appropriate. This example places the /var directory on a separate partition:

    1. variant: openshift
    2. version: 4.14.0
    3. metadata:
    4. labels:
    5. machineconfiguration.openshift.io/role: worker
    6. name: 98-var-partition
    7. storage:
    8. disks:
    9. - device: /dev/disk/by-id/<device_name> (1)
    10. partitions:
    11. - label: var
    12. start_mib: <partition_start_offset> (2)
    13. size_mib: <partition_size> (3)
    14. filesystems:
    15. - device: /dev/disk/by-partlabel/var
    16. path: /var
    17. format: xfs
    18. mount_options: [defaults, prjquota] (4)
    19. with_mount_unit: true
    1The storage device name of the disk that you want to partition.
    2When adding a data partition to the boot disk, a minimum value of 25000 mebibytes is recommended. The root file system is automatically resized to fill all available space up to the specified offset. If no value is specified, or if the specified value is smaller than the recommended minimum, the resulting root file system will be too small, and future reinstalls of FCOS might overwrite the beginning of the data partition.
    3The size of the data partition in mebibytes.
    4The prjquota mount option must be enabled for filesystems used for container storage.

    When creating a separate /var partition, you cannot use different instance types for worker nodes, if the different instance types do not have the same device name.

  4. Create a manifest from the Butane config and save it to the clusterconfig/openshift directory. For example, run the following command:

    1. $ butane $HOME/clusterconfig/98-var-partition.bu -o $HOME/clusterconfig/openshift/98-var-partition.yaml
  5. Run openshift-install again to create Ignition configs from a set of files in the manifest and openshift subdirectories:

    1. $ openshift-install create ignition-configs --dir $HOME/clusterconfig
    2. $ ls $HOME/clusterconfig/
    3. auth bootstrap.ign master.ign metadata.json worker.ign

Now you can use the Ignition config files as input to the vSphere installation procedures to install Fedora CoreOS (FCOS) systems.

Updating the bootloader using bootupd

To update the bootloader by using bootupd, you must either install bootupd on FCOS machines manually or provide a machine config with the enabled systemd unit. Unlike grubby or other bootloader tools, bootupd does not manage kernel space configuration such as passing kernel arguments.

After you have installed bootupd, you can manage it remotely from the OKD cluster.

It is recommended that you use bootupd only on bare metal or virtualized hypervisor installations, such as for protection against the BootHole vulnerability.

Manual install method

You can manually install bootupd by using the bootctl command-line tool.

  1. Inspect the system status:

    1. # bootupctl status

    Example output for x86_64

    1. Component EFI
    2. Installed: grub2-efi-x64-1:2.04-31.fc33.x86_64,shim-x64-15-8.x86_64
    3. Update: At latest version
  2. FCOS images created without bootupd installed on them require an explicit adoption phase.

    If the system status is Adoptable, perform the adoption:

    1. # bootupctl adopt-and-update

    Example output

    1. Updated: grub2-efi-x64-1:2.04-31.fc33.x86_64,shim-x64-15-8.x86_64
  3. If an update is available, apply the update so that the changes take effect on the next reboot:

    1. # bootupctl update

    Example output

    1. Updated: grub2-efi-x64-1:2.04-31.fc33.x86_64,shim-x64-15-8.x86_64

Machine config method

Another way to enable bootupd is by providing a machine config.

  • Provide a machine config file with the enabled systemd unit, as shown in the following example:

    Example output

    1. variant: rhcos
    2. version: 1.1.0
    3. systemd:
    4. units:
    5. - name: custom-bootupd-auto.service
    6. enabled: true
    7. contents: |
    8. [Unit]
    9. Description=Bootupd automatic update
    10. [Service]
    11. ExecStart=/usr/bin/bootupctl update
    12. RemainAfterExit=yes
    13. [Install]
    14. WantedBy=multi-user.target

Waiting for the bootstrap process to complete

The OKD bootstrap process begins after the cluster nodes first boot into the persistent FCOS environment that has been installed to disk. The configuration information provided through the Ignition config files is used to initialize the bootstrap process and install OKD on the machines. You must wait for the bootstrap process to complete.

Prerequisites

  • You have created the Ignition config files for your cluster.

  • You have configured suitable network, DNS and load balancing infrastructure.

  • You have obtained the installation program and generated the Ignition config files for your cluster.

  • You installed FCOS on your cluster machines and provided the Ignition config files that the OKD installation program generated.

Procedure

  1. Monitor the bootstrap process:

    1. $ ./openshift-install --dir <installation_directory> wait-for bootstrap-complete \ (1)
    2. --log-level=info (2)
    1For <installation_directory>, specify the path to the directory that you stored the installation files in.
    2To view different installation details, specify warn, debug, or error instead of info.

    Example output

    1. INFO Waiting up to 30m0s for the Kubernetes API at https://api.test.example.com:6443...
    2. INFO API v1.27.3 up
    3. INFO Waiting up to 30m0s for bootstrapping to complete...
    4. INFO It is now safe to remove the bootstrap resources

    The command succeeds when the Kubernetes API server signals that it has been bootstrapped on the control plane machines.

  2. After the bootstrap process is complete, remove the bootstrap machine from the load balancer.

    You must remove the bootstrap machine from the load balancer at this point. You can also remove or reformat the bootstrap machine itself.

Logging in to the cluster by using the CLI

You can log in to your cluster as a default system user by exporting the cluster kubeconfig file. The kubeconfig file contains information about the cluster that is used by the CLI to connect a client to the correct cluster and API server. The file is specific to a cluster and is created during OKD installation.

Prerequisites

  • You deployed an OKD cluster.

  • You installed the oc CLI.

Procedure

  1. Export the kubeadmin credentials:

    1. $ export KUBECONFIG=<installation_directory>/auth/kubeconfig (1)
    1For <installation_directory>, specify the path to the directory that you stored the installation files in.
  2. Verify you can run oc commands successfully using the exported configuration:

    1. $ oc whoami

    Example output

    1. system:admin

Approving the certificate signing requests for your machines

When you add machines to a cluster, two pending certificate signing requests (CSRs) are generated for each machine that you added. You must confirm that these CSRs are approved or, if necessary, approve them yourself. The client requests must be approved first, followed by the server requests.

Prerequisites

  • You added machines to your cluster.

Procedure

  1. Confirm that the cluster recognizes the machines:

    1. $ oc get nodes

    Example output

    1. NAME STATUS ROLES AGE VERSION
    2. master-0 Ready master 63m v1.27.3
    3. master-1 Ready master 63m v1.27.3
    4. master-2 Ready master 64m v1.27.3

    The output lists all of the machines that you created.

    The preceding output might not include the compute nodes, also known as worker nodes, until some CSRs are approved.

  2. Review the pending CSRs and ensure that you see the client requests with the Pending or Approved status for each machine that you added to the cluster:

    1. $ oc get csr

    Example output

    1. NAME AGE REQUESTOR CONDITION
    2. csr-8b2br 15m system:serviceaccount:openshift-machine-config-operator:node-bootstrapper Pending
    3. csr-8vnps 15m system:serviceaccount:openshift-machine-config-operator:node-bootstrapper Pending
    4. ...

    In this example, two machines are joining the cluster. You might see more approved CSRs in the list.

  3. If the CSRs were not approved, after all of the pending CSRs for the machines you added are in Pending status, approve the CSRs for your cluster machines:

    Because the CSRs rotate automatically, approve your CSRs within an hour of adding the machines to the cluster. If you do not approve them within an hour, the certificates will rotate, and more than two certificates will be present for each node. You must approve all of these certificates. After the client CSR is approved, the Kubelet creates a secondary CSR for the serving certificate, which requires manual approval. Then, subsequent serving certificate renewal requests are automatically approved by the machine-approver if the Kubelet requests a new certificate with identical parameters.

    For clusters running on platforms that are not machine API enabled, such as bare metal and other user-provisioned infrastructure, you must implement a method of automatically approving the kubelet serving certificate requests (CSRs). If a request is not approved, then the oc exec, oc rsh, and oc logs commands cannot succeed, because a serving certificate is required when the API server connects to the kubelet. Any operation that contacts the Kubelet endpoint requires this certificate approval to be in place. The method must watch for new CSRs, confirm that the CSR was submitted by the node-bootstrapper service account in the system:node or system:admin groups, and confirm the identity of the node.

    • To approve them individually, run the following command for each valid CSR:

      1. $ oc adm certificate approve <csr_name> (1)
      1<csr_name> is the name of a CSR from the list of current CSRs.
    • To approve all pending CSRs, run the following command:

      1. $ oc get csr -o go-template='{{range .items}}{{if not .status}}{{.metadata.name}}{{"\n"}}{{end}}{{end}}' | xargs --no-run-if-empty oc adm certificate approve

      Some Operators might not become available until some CSRs are approved.

  4. Now that your client requests are approved, you must review the server requests for each machine that you added to the cluster:

    1. $ oc get csr

    Example output

    1. NAME AGE REQUESTOR CONDITION
    2. csr-bfd72 5m26s system:node:ip-10-0-50-126.us-east-2.compute.internal Pending
    3. csr-c57lv 5m26s system:node:ip-10-0-95-157.us-east-2.compute.internal Pending
    4. ...
  5. If the remaining CSRs are not approved, and are in the Pending status, approve the CSRs for your cluster machines:

    • To approve them individually, run the following command for each valid CSR:

      1. $ oc adm certificate approve <csr_name> (1)
      1<csr_name> is the name of a CSR from the list of current CSRs.
    • To approve all pending CSRs, run the following command:

      1. $ oc get csr -o go-template='{{range .items}}{{if not .status}}{{.metadata.name}}{{"\n"}}{{end}}{{end}}' | xargs oc adm certificate approve
  6. After all client and server CSRs have been approved, the machines have the Ready status. Verify this by running the following command:

    1. $ oc get nodes

    Example output

    1. NAME STATUS ROLES AGE VERSION
    2. master-0 Ready master 73m v1.27.3
    3. master-1 Ready master 73m v1.27.3
    4. master-2 Ready master 74m v1.27.3
    5. worker-0 Ready worker 11m v1.27.3
    6. worker-1 Ready worker 11m v1.27.3

    It can take a few minutes after approval of the server CSRs for the machines to transition to the Ready status.

Additional information

Initial Operator configuration

After the control plane initializes, you must immediately configure some Operators so that they all become available.

Prerequisites

  • Your control plane has initialized.

Procedure

  1. Watch the cluster components come online:

    1. $ watch -n5 oc get clusteroperators

    Example output

    1. NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE
    2. authentication 4.14.0 True False False 19m
    3. baremetal 4.14.0 True False False 37m
    4. cloud-credential 4.14.0 True False False 40m
    5. cluster-autoscaler 4.14.0 True False False 37m
    6. config-operator 4.14.0 True False False 38m
    7. console 4.14.0 True False False 26m
    8. csi-snapshot-controller 4.14.0 True False False 37m
    9. dns 4.14.0 True False False 37m
    10. etcd 4.14.0 True False False 36m
    11. image-registry 4.14.0 True False False 31m
    12. ingress 4.14.0 True False False 30m
    13. insights 4.14.0 True False False 31m
    14. kube-apiserver 4.14.0 True False False 26m
    15. kube-controller-manager 4.14.0 True False False 36m
    16. kube-scheduler 4.14.0 True False False 36m
    17. kube-storage-version-migrator 4.14.0 True False False 37m
    18. machine-api 4.14.0 True False False 29m
    19. machine-approver 4.14.0 True False False 37m
    20. machine-config 4.14.0 True False False 36m
    21. marketplace 4.14.0 True False False 37m
    22. monitoring 4.14.0 True False False 29m
    23. network 4.14.0 True False False 38m
    24. node-tuning 4.14.0 True False False 37m
    25. openshift-apiserver 4.14.0 True False False 32m
    26. openshift-controller-manager 4.14.0 True False False 30m
    27. openshift-samples 4.14.0 True False False 32m
    28. operator-lifecycle-manager 4.14.0 True False False 37m
    29. operator-lifecycle-manager-catalog 4.14.0 True False False 37m
    30. operator-lifecycle-manager-packageserver 4.14.0 True False False 32m
    31. service-ca 4.14.0 True False False 38m
    32. storage 4.14.0 True False False 37m
  2. Configure the Operators that are not available.

Disabling the default OperatorHub catalog sources

Operator catalogs that source content provided by Red Hat and community projects are configured for OperatorHub by default during an OKD installation. In a restricted network environment, you must disable the default catalogs as a cluster administrator.

Procedure

  • Disable the sources for the default catalogs by adding disableAllDefaultSources: true to the OperatorHub object:

    1. $ oc patch OperatorHub cluster --type json \
    2. -p '[{"op": "add", "path": "/spec/disableAllDefaultSources", "value": true}]'

Alternatively, you can use the web console to manage catalog sources. From the AdministrationCluster SettingsConfigurationOperatorHub page, click the Sources tab, where you can create, update, delete, disable, and enable individual sources.

Image registry storage configuration

The Image Registry Operator is not initially available for platforms that do not provide default storage. After installation, you must configure your registry to use storage so that the Registry Operator is made available.

Instructions are shown for configuring a persistent volume, which is required for production clusters. Where applicable, instructions are shown for configuring an empty directory as the storage location, which is available for only non-production clusters.

Additional instructions are provided for allowing the image registry to use block storage types by using the Recreate rollout strategy during upgrades.

Configuring registry storage for VMware vSphere

As a cluster administrator, following installation you must configure your registry to use storage.

Prerequisites

  • Cluster administrator permissions.

  • A cluster on VMware vSphere.

  • Persistent storage provisioned for your cluster, such as Red Hat OpenShift Data Foundation.

    OKD supports ReadWriteOnce access for image registry storage when you have only one replica. ReadWriteOnce access also requires that the registry uses the Recreate rollout strategy. To deploy an image registry that supports high availability with two or more replicas, ReadWriteMany access is required.

  • Must have “100Gi” capacity.

Testing shows issues with using the NFS server on RHEL as storage backend for core services. This includes the OpenShift Container Registry and Quay, Prometheus for monitoring storage, and Elasticsearch for logging storage. Therefore, using RHEL NFS to back PVs used by core services is not recommended.

Other NFS implementations on the marketplace might not have these issues. Contact the individual NFS implementation vendor for more information on any testing that was possibly completed against these OKD core components.

Procedure

  1. To configure your registry to use storage, change the spec.storage.pvc in the configs.imageregistry/cluster resource.

    When you use shared storage, review your security settings to prevent outside access.

  2. Verify that you do not have a registry pod:

    1. $ oc get pod -n openshift-image-registry -l docker-registry=default

    Example output

    1. No resourses found in openshift-image-registry namespace

    If you do have a registry pod in your output, you do not need to continue with this procedure.

  3. Check the registry configuration:

    1. $ oc edit configs.imageregistry.operator.openshift.io

    Example output

    1. storage:
    2. pvc:
    3. claim: (1)
    1Leave the claim field blank to allow the automatic creation of an image-registry-storage persistent volume claim (PVC). The PVC is generated based on the default storage class. However, be aware that the default storage class might provide ReadWriteOnce (RWO) volumes, such as a RADOS Block Device (RBD), which can cause issues when you replicate to more than one replica.
  4. Check the clusteroperator status:

    1. $ oc get clusteroperator image-registry

    Example output

    1. NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE MESSAGE
    2. image-registry 4.7 True False False 6h50m

Configuring storage for the image registry in non-production clusters

You must configure storage for the Image Registry Operator. For non-production clusters, you can set the image registry to an empty directory. If you do so, all images are lost if you restart the registry.

Procedure

  • To set the image registry storage to an empty directory:

    1. $ oc patch configs.imageregistry.operator.openshift.io cluster --type merge --patch '{"spec":{"storage":{"emptyDir":{}}}}'

    Configure this option for only non-production clusters.

    If you run this command before the Image Registry Operator initializes its components, the oc patch command fails with the following error:

    1. Error from server (NotFound): configs.imageregistry.operator.openshift.io "cluster" not found

    Wait a few minutes and run the command again.

Configuring block registry storage for VMware vSphere

To allow the image registry to use block storage types such as vSphere Virtual Machine Disk (VMDK) during upgrades as a cluster administrator, you can use the Recreate rollout strategy.

Block storage volumes are supported but not recommended for use with image registry on production clusters. An installation where the registry is configured on block storage is not highly available because the registry cannot have more than one replica.

Procedure

  1. To set the image registry storage as a block storage type, patch the registry so that it uses the Recreate rollout strategy and runs with only 1 replica:

    1. $ oc patch config.imageregistry.operator.openshift.io/cluster --type=merge -p '{"spec":{"rolloutStrategy":"Recreate","replicas":1}}'
  2. Provision the PV for the block storage device, and create a PVC for that volume. The requested block volume uses the ReadWriteOnce (RWO) access mode.

    1. Create a pvc.yaml file with the following contents to define a VMware vSphere PersistentVolumeClaim object:

      1. kind: PersistentVolumeClaim
      2. apiVersion: v1
      3. metadata:
      4. name: image-registry-storage (1)
      5. namespace: openshift-image-registry (2)
      6. spec:
      7. accessModes:
      8. - ReadWriteOnce (3)
      9. resources:
      10. requests:
      11. storage: 100Gi (4)
      1A unique name that represents the PersistentVolumeClaim object.
      2The namespace for the PersistentVolumeClaim object, which is openshift-image-registry.
      3The access mode of the persistent volume claim. With ReadWriteOnce, the volume can be mounted with read and write permissions by a single node.
      4The size of the persistent volume claim.
    2. Create the PersistentVolumeClaim object from the file:

      1. $ oc create -f pvc.yaml -n openshift-image-registry
  3. Edit the registry configuration so that it references the correct PVC:

    1. $ oc edit config.imageregistry.operator.openshift.io -o yaml

    Example output

    1. storage:
    2. pvc:
    3. claim: (1)
    1By creating a custom PVC, you can leave the claim field blank for the default automatic creation of an image-registry-storage PVC.

For instructions about configuring registry storage so that it references the correct PVC, see Configuring the registry for vSphere.

Completing installation on user-provisioned infrastructure

After you complete the Operator configuration, you can finish installing the cluster on infrastructure that you provide.

Prerequisites

  • Your control plane has initialized.

  • You have completed the initial Operator configuration.

Procedure

  1. Confirm that all the cluster components are online with the following command:

    1. $ watch -n5 oc get clusteroperators

    Example output

    1. NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE
    2. authentication 4.14.0 True False False 19m
    3. baremetal 4.14.0 True False False 37m
    4. cloud-credential 4.14.0 True False False 40m
    5. cluster-autoscaler 4.14.0 True False False 37m
    6. config-operator 4.14.0 True False False 38m
    7. console 4.14.0 True False False 26m
    8. csi-snapshot-controller 4.14.0 True False False 37m
    9. dns 4.14.0 True False False 37m
    10. etcd 4.14.0 True False False 36m
    11. image-registry 4.14.0 True False False 31m
    12. ingress 4.14.0 True False False 30m
    13. insights 4.14.0 True False False 31m
    14. kube-apiserver 4.14.0 True False False 26m
    15. kube-controller-manager 4.14.0 True False False 36m
    16. kube-scheduler 4.14.0 True False False 36m
    17. kube-storage-version-migrator 4.14.0 True False False 37m
    18. machine-api 4.14.0 True False False 29m
    19. machine-approver 4.14.0 True False False 37m
    20. machine-config 4.14.0 True False False 36m
    21. marketplace 4.14.0 True False False 37m
    22. monitoring 4.14.0 True False False 29m
    23. network 4.14.0 True False False 38m
    24. node-tuning 4.14.0 True False False 37m
    25. openshift-apiserver 4.14.0 True False False 32m
    26. openshift-controller-manager 4.14.0 True False False 30m
    27. openshift-samples 4.14.0 True False False 32m
    28. operator-lifecycle-manager 4.14.0 True False False 37m
    29. operator-lifecycle-manager-catalog 4.14.0 True False False 37m
    30. operator-lifecycle-manager-packageserver 4.14.0 True False False 32m
    31. service-ca 4.14.0 True False False 38m
    32. storage 4.14.0 True False False 37m

    Alternatively, the following command notifies you when all of the clusters are available. It also retrieves and displays credentials:

    1. $ ./openshift-install --dir <installation_directory> wait-for install-complete (1)
    1For <installation_directory>, specify the path to the directory that you stored the installation files in.

    Example output

    1. INFO Waiting up to 30m0s for the cluster to initialize...

    The command succeeds when the Cluster Version Operator finishes deploying the OKD cluster from Kubernetes API server.

    • The Ignition config files that the installation program generates contain certificates that expire after 24 hours, which are then renewed at that time. If the cluster is shut down before renewing the certificates and the cluster is later restarted after the 24 hours have elapsed, the cluster automatically recovers the expired certificates. The exception is that you must manually approve the pending node-bootstrapper certificate signing requests (CSRs) to recover kubelet certificates. See the documentation for Recovering from expired control plane certificates for more information.

    • It is recommended that you use Ignition config files within 12 hours after they are generated because the 24-hour certificate rotates from 16 to 22 hours after the cluster is installed. By using the Ignition config files within 12 hours, you can avoid installation failure if the certificate update runs during installation.

  2. Confirm that the Kubernetes API server is communicating with the pods.

    1. To view a list of all pods, use the following command:

      1. $ oc get pods --all-namespaces

      Example output

      1. NAMESPACE NAME READY STATUS RESTARTS AGE
      2. openshift-apiserver-operator openshift-apiserver-operator-85cb746d55-zqhs8 1/1 Running 1 9m
      3. openshift-apiserver apiserver-67b9g 1/1 Running 0 3m
      4. openshift-apiserver apiserver-ljcmx 1/1 Running 0 1m
      5. openshift-apiserver apiserver-z25h4 1/1 Running 0 2m
      6. openshift-authentication-operator authentication-operator-69d5d8bf84-vh2n8 1/1 Running 0 5m
      7. ...
    2. View the logs for a pod that is listed in the output of the previous command by using the following command:

      1. $ oc logs <pod_name> -n <namespace> (1)
      1Specify the pod name and namespace, as shown in the output of the previous command.

      If the pod logs display, the Kubernetes API server can communicate with the cluster machines.

  3. For an installation with Fibre Channel Protocol (FCP), additional steps are required to enable multipathing. Do not enable multipathing during installation.

    See “Enabling multipathing with kernel arguments on FCOS” in the Post-installation machine configuration tasks documentation for more information.

  4. Register your cluster on the Cluster registration page.

You can add extra compute machines after the cluster installation is completed by following Adding compute machines to vSphere.

Configuring vSphere DRS anti-affinity rules for control plane nodes

vSphere Distributed Resource Scheduler (DRS) anti-affinity rules can be configured to support higher availability of OKD Control Plane nodes. Anti-affinity rules ensure that the vSphere Virtual Machines for the OKD Control Plane nodes are not scheduled to the same vSphere Host.

  • The following information applies to compute DRS only and does not apply to storage DRS.

  • The govc command is an open-source command available from VMware; it is not available from Red Hat. The govc command is not supported by the Red Hat support.

  • Instructions for downloading and installing govc are found on the VMware documentation website.

Create an anti-affinity rule by running the following command:

Example command

  1. $ govc cluster.rule.create \
  2. -name openshift4-control-plane-group \
  3. -dc MyDatacenter -cluster MyCluster \
  4. -enable \
  5. -anti-affinity master-0 master-1 master-2

After creating the rule, your control plane nodes are automatically migrated by vSphere so they are not running on the same hosts. This might take some time while vSphere reconciles the new rule. Successful command completion is shown in the following procedure.

The migration occurs automatically and might cause brief OpenShift API outage or latency until the migration finishes.

The vSphere DRS anti-affinity rules need to be updated manually in the event of a control plane VM name change or migration to a new vSphere Cluster.

Procedure

  1. Remove any existing DRS anti-affinity rule by running the following command:

    1. $ govc cluster.rule.remove \
    2. -name openshift4-control-plane-group \
    3. -dc MyDatacenter -cluster MyCluster

    Example Output

    1. [13-10-22 09:33:24] Reconfigure /MyDatacenter/host/MyCluster...OK
  2. Create the rule again with updated names by running the following command:

    1. $ govc cluster.rule.create \
    2. -name openshift4-control-plane-group \
    3. -dc MyDatacenter -cluster MyOtherCluster \
    4. -enable \
    5. -anti-affinity master-0 master-1 master-2

Backing up VMware vSphere volumes

OKD provisions new volumes as independent persistent disks to freely attach and detach the volume on any node in the cluster. As a consequence, it is not possible to back up volumes that use snapshots, or to restore volumes from snapshots. See Snapshot Limitations for more information.

Procedure

To create a backup of persistent volumes:

  1. Stop the application that is using the persistent volume.

  2. Clone the persistent volume.

  3. Restart the application.

  4. Create a backup of the cloned volume.

  5. Delete the cloned volume.

Additional resources

Next steps