Chapter 9. Monitoring a high availability Red Hat Ceph Storage cluster

When you deploy an overcloud with Red Hat Ceph Storage, Red Hat OpenStack Platform uses the ceph-mon monitor daemon to manage the Ceph cluster. Director deploys the daemon on all Controller nodes.

View the status of the Ceph Monitoring service

On a Controller node, run the service ceph status command to check that the Ceph Monitoring service is running:

$ sudo service ceph status
=== mon.overcloud-controller-0 ===
mon.overcloud-controller-0: running {"version":"0.94.1"}

View Ceph Monitoring configuration

On a Controller nodes or on a Ceph node, open the /etc/ceph/ceph.conf file to view the monitoring configuration parameters:

[global]
osd_pool_default_pgp_num = 128
osd_pool_default_min_size = 1
auth_service_required = cephx
mon_initial_members = overcloud-controller-0,overcloud-controller-1,overcloud-controller-2
fsid = 8c835acc-6838-11e5-bb96-2cc260178a92
cluster_network = 172.19.0.11/24
auth_supported = cephx
auth_cluster_required = cephx
mon_host = 172.18.0.17,172.18.0.15,172.18.0.16
auth_client_required = cephx
osd_pool_default_size = 3
osd_pool_default_pg_num = 128
public_network = 172.18.0.17/24

This example shows the following information:

  • All three Controller nodes are configured to monitor the Red Hat Ceph Storage cluster with the mon_initial_members parameter.
  • The 172.19.0.11/24 network is configured to provide a communication path between the Controller nodes and the Red Hat Ceph Storage nodes.
  • The Red Hat Ceph Storage nodes are assigned to a separate network from the Controller nodes, and the IP addresses for the monitoring Controller nodes are 172.18.0.15, 172.18.0.16, and 172.18.0.17.

View individual Ceph node status

Log in to the Ceph node and run the ceph -s command:

# ceph -s
    cluster 8c835acc-6838-11e5-bb96-2cc260178a92
     health HEALTH_OK
     monmap e1: 3 mons at {overcloud-controller-0=172.18.0.17:6789/0,overcloud-controller-1=172.18.0.15:6789/0,overcloud-controller-2=172.18.0.16:6789/0}
            election epoch 152, quorum 0,1,2 overcloud-controller-1,overcloud-controller-2,overcloud-controller-0
     osdmap e543: 6 osds: 6 up, 6 in
      pgmap v1736: 256 pgs, 4 pools, 0 bytes data, 0 objects
            267 MB used, 119 GB / 119 GB avail
                 256 active+clean

This example output shows that the health parameter value is HEALTH_OK, which indicates that the Ceph node is active and healthy. The output also shows three Ceph monitor services that are running on the three overcloud-controller nodes and the IP addresses and ports of the services.

For more information about Red Hat Ceph Storage, see the Red Hat Ceph product page.