Before proceeding with the cluster size reduction, scaling it down, or removing the OSD node, make sure that the cluster has enough free space to accommodate all the data present on the node you are planning to move out. The cluster should not be at its full ratio, which is the percentage of used disk space in an OSD. So, as best practice, do not remove the OSD or OSD node without considering the impact on the full ratio. At the current time of writing this book Ceph-Ansible does not support scaling down of the Ceph OSD nodes in a cluster and this must be done manually.
- As we need to scale down the cluster, we will remove ceph-node4 and all of its associated OSDs out of the cluster. Ceph OSDs should be set out so that ...