This guide will detail the process of adding OSD nodes to an existing cluster running RedHat Enterprise Storage 4 (Nautilus). The process can be completed without taking the cluster out of production.
Set ceph cluster into maintenance mode
ceph osd set norebalance
ceph osd set nobackfill
ceph osd set norecover
Verify ceph cluster status
ceph status
Make sure that the new ceph node is defined in the /etc/hosts file.
vim /usr/share/ceph-ansible/hosts
[mons]
...
[mgrs]
...
[osds]
ceph-node1
ceph-node2
ceph-node3
ceph-node4
...
ping test before ansible playbook execution
ansible-playbook site-conatiner.yml --limit ceph-node4
unset maintenance mode
ceph osd unset nobackfill
ceph osd unset norecover
ceph osd unset norebalance
verify added Check that all Osds with hard drives have been added as expected
ceph osd tree
ceph osd crush tree
ceph osd df
ceph -s
verify all services uses the same version
ceph versions
sources
docs.ceph.com/projects/ceph-ansible/en/latest/day-2/osds.html