Ceph Cheatsheet

Here is a cheatsheet of things you can do once you have a deployed a cluster.

Cluster Health

You can check the cluser's health with the following command:

ceph health

That should have returned: HEALTH_OK

More detailed information can be fetched using the command ceph status which will return something like below:

    cluster 188c4e2e-126b-4e40-99a3-f4393467a4d4
     health HEALTH_OK
     monmap e1: 1 mons at {ceph-mon1=10.1.0.100:6789/0}, election epoch 2, quorum 0 ceph-mon1
     osdmap e14: 3 osds: 3 up, 3 in
      pgmap v30: 192 pgs, 3 pools, 0 bytes data, 0 objects
            31264 MB used, 53603 MB / 89481 MB avail
                 192 active+clean

Creating a block device

rbd create {image-name} --size {megabytes}

e.g. To create a 1Gb block device

rbd create bar --size 1024

You should now be able to see the block device by listing them:

rbd ls