Ceph: Designing and Implementing Scalable Storage Systems

Removing the Ceph MON

Removing a Ceph MON is generally not a very frequently required task. When you remove monitors from a cluster, consider that Ceph monitors use the PAXOS algorithm to establish consensus about the master cluster map. You must have a sufficient number of monitors to establish a quorum for consensus on the cluster map. In this recipe, we will learn how to remove the ceph-node4 monitor from the Ceph cluster. At the current time of writing this book, ceph-ansible does not support scaling down of Ceph MON nodes in a cluster and this must be done manually.

1. Check the monitor status:

# ceph mon stat

2. Stop the monitor service ...