Common Settings

The Hardware Recommendations section provides some hardware guidelines forconfiguring a Ceph Storage Cluster. It is possible for a single CephNode to run multiple daemons. For example, a single node with multiple drivesmay run one ceph-osd for each drive. Ideally, you will have a node for aparticular type of process. For example, some nodes may run ceph-osddaemons, other nodes may run ceph-mds daemons, and still other nodes mayrun ceph-mon daemons.

Each node has a name identified by the host setting. Monitors also specifya network address and port (i.e., domain name or IP address) identified by theaddr setting. A basic configuration file will typically specify onlyminimal settings for each instance of monitor daemons. For example:

[global]
mon_initial_members = ceph1
mon_host = 10.0.0.1

Important

The host setting is the short name of the node (i.e., notan fqdn). It is NOT an IP address either. Enter hostname -s onthe command line to retrieve the name of the node. Do not use hostsettings for anything other than initial monitors unless you are deployingCeph manually. You MUST NOT specify host under individual daemonswhen using deployment tools like chef or ceph-deploy, as those toolswill enter the appropriate values for you in the cluster map.