kubeadm upgrade

kubeadm upgrade is a user-friendly command that wraps complex upgrading logic behind one command, with support for both planning an upgrade and actually performing it.

kubeadm upgrade guidance

The steps for performing a upgrade using kubeadm are outlined in this document. For older versions of kubeadm, please refer to older documentation sets of the Kubernetes website.

You can use kubeadm upgrade diff to see the changes that would be applied to static pod manifests.

To use kube-dns with upgrades in Kubernetes v1.13.0 and later please follow this guide.

In Kubernetes v1.15.0 and later, kubeadm upgrade apply and kubeadm upgrade node will also automatically renew the kubeadm managed certificates on this node, including those stored in kubeconfig files. To opt-out, it is possible to pass the flag --certificate-renewal=false. For more details about certificate renewal see the certificate management documentation.

Note: The commands kubeadm upgrade apply and kubeadm upgrade plan have a legacy --config flag which makes it possible to reconfigure the cluster, while performing planning or upgrade of that particular control-plane node. Please be aware that the upgrade workflow was not designed for this scenario and there are reports of unexpected results.

kubeadm upgrade plan

Synopsis

Check which versions are available to upgrade to and validate whether your current cluster is upgradeable. To skip the internet check, pass in the optional [version] parameter

  1. kubeadm upgrade plan [version] [flags]

Options

—allow-experimental-upgrades
Show unstable versions of Kubernetes as an upgrade alternative and allow upgrading to an alpha/beta/release candidate versions of Kubernetes.
—allow-release-candidate-upgrades
Show release candidate versions of Kubernetes as an upgrade alternative and allow upgrading to a release candidate versions of Kubernetes.
—config string
Path to a kubeadm configuration file.
—feature-gates string
A set of key=value pairs that describe feature gates for various features. Options are:
IPv6DualStack=true|false (ALPHA - default=false)
PublicKeysECDSA=true|false (ALPHA - default=false)
-h, —help
help for plan
—ignore-preflight-errors stringSlice
A list of checks whose errors will be shown as warnings. Example: ‘IsPrivilegedUser,Swap’. Value ‘all’ ignores errors from all checks.
—kubeconfig string     Default: “/etc/kubernetes/admin.conf”
The kubeconfig file to use when talking to the cluster. If the flag is not set, a set of standard locations can be searched for an existing kubeconfig file.
—print-config
Specifies whether the configuration file that will be used in the upgrade should be printed or not.

Options inherited from parent commands

—rootfs string
[EXPERIMENTAL] The path to the ‘real’ host root filesystem.

kubeadm upgrade apply

Synopsis

Upgrade your Kubernetes cluster to the specified version

  1. kubeadm upgrade apply [version]

Options

—allow-experimental-upgrades
Show unstable versions of Kubernetes as an upgrade alternative and allow upgrading to an alpha/beta/release candidate versions of Kubernetes.
—allow-release-candidate-upgrades
Show release candidate versions of Kubernetes as an upgrade alternative and allow upgrading to a release candidate versions of Kubernetes.
—certificate-renewal     Default: true
Perform the renewal of certificates used by component changed during upgrades.
—config string
Path to a kubeadm configuration file.
—dry-run
Do not change any state, just output what actions would be performed.
—etcd-upgrade     Default: true
Perform the upgrade of etcd.
—experimental-patches string
Path to a directory that contains files named “target[suffix][+patchtype].extension”. For example, “kube-apiserver0+merge.yaml” or just “etcd.json”. “patchtype” can be one of “strategic”, “merge” or “json” and they match the patch formats supported by kubectl. The default “patchtype” is “strategic”. “extension” must be either “json” or “yaml”. “suffix” is an optional string that can be used to determine which patches are applied first alpha-numerically.
—feature-gates string
A set of key=value pairs that describe feature gates for various features. Options are:
IPv6DualStack=true|false (ALPHA - default=false)
PublicKeysECDSA=true|false (ALPHA - default=false)
-f, —force
Force upgrading although some requirements might not be met. This also implies non-interactive mode.
-h, —help
help for apply
—ignore-preflight-errors stringSlice
A list of checks whose errors will be shown as warnings. Example: ‘IsPrivilegedUser,Swap’. Value ‘all’ ignores errors from all checks.
—kubeconfig string     Default: “/etc/kubernetes/admin.conf”
The kubeconfig file to use when talking to the cluster. If the flag is not set, a set of standard locations can be searched for an existing kubeconfig file.
—print-config
Specifies whether the configuration file that will be used in the upgrade should be printed or not.
-y, —yes
Perform the upgrade and do not prompt for confirmation (non-interactive mode).

Options inherited from parent commands

—rootfs string
[EXPERIMENTAL] The path to the ‘real’ host root filesystem.

kubeadm upgrade diff

Synopsis

Show what differences would be applied to existing static pod manifests. See also: kubeadm upgrade apply —dry-run

  1. kubeadm upgrade diff [version] [flags]

Options

—api-server-manifest string     Default: “/etc/kubernetes/manifests/kube-apiserver.yaml”
path to API server manifest
—config string
Path to a kubeadm configuration file.
-c, —context-lines int     Default: 3
How many lines of context in the diff
—controller-manager-manifest string     Default: “/etc/kubernetes/manifests/kube-controller-manager.yaml”
path to controller manifest
-h, —help
help for diff
—kubeconfig string     Default: “/etc/kubernetes/admin.conf”
The kubeconfig file to use when talking to the cluster. If the flag is not set, a set of standard locations can be searched for an existing kubeconfig file.
—scheduler-manifest string     Default: “/etc/kubernetes/manifests/kube-scheduler.yaml”
path to scheduler manifest

Options inherited from parent commands

—rootfs string
[EXPERIMENTAL] The path to the ‘real’ host root filesystem.

kubeadm upgrade node

Synopsis

Upgrade commands for a node in the cluster

The “node” command executes the following phases:

  1. preflight Run upgrade node pre-flight checks
  2. control-plane Upgrade the control plane instance deployed on this node, if any
  3. kubelet-config Upgrade the kubelet configuration for this node
  1. kubeadm upgrade node [flags]

Options

—certificate-renewal     Default: true
Perform the renewal of certificates used by component changed during upgrades.
—dry-run
Do not change any state, just output the actions that would be performed.
—etcd-upgrade     Default: true
Perform the upgrade of etcd.
—experimental-patches string
Path to a directory that contains files named “target[suffix][+patchtype].extension”. For example, “kube-apiserver0+merge.yaml” or just “etcd.json”. “patchtype” can be one of “strategic”, “merge” or “json” and they match the patch formats supported by kubectl. The default “patchtype” is “strategic”. “extension” must be either “json” or “yaml”. “suffix” is an optional string that can be used to determine which patches are applied first alpha-numerically.
-h, —help
help for node
—ignore-preflight-errors stringSlice
A list of checks whose errors will be shown as warnings. Example: ‘IsPrivilegedUser,Swap’. Value ‘all’ ignores errors from all checks.
—kubeconfig string     Default: “/etc/kubernetes/admin.conf”
The kubeconfig file to use when talking to the cluster. If the flag is not set, a set of standard locations can be searched for an existing kubeconfig file.
—skip-phases stringSlice
List of phases to be skipped

Options inherited from parent commands

—rootfs string
[EXPERIMENTAL] The path to the ‘real’ host root filesystem.

What’s next

  • kubeadm config if you initialized your cluster using kubeadm v1.7.x or lower, to configure your cluster for kubeadm upgrade