Install Ceph on Proxmox cluster node

[William Edwards]

Assuming an existing Proxmox cluster with node1, node2, node3 and node4:

• node1, node2 and node3 are used as Ceph monitors, managers, MDSes and OSD nodes.
• node4 is already in the Proxmox cluster, but is only used as a 'compute' node; pveceph is not installed.
• So: node1 to node4 are in the Proxmox cluster, but only node1 to node3 are in the Ceph cluster. node4 simply uses the Ceph cluster on the other nodes in the Proxmox cluster.

Is the proper way to let node4 join the Ceph cluster to simply `pveceph install` on node4? My concern with that is that 'pveceph' could create a new pool, and overwrite the data/pool in the existing Ceph cluster. Or would that not overwrite anything because `/etc/pve/ceph.conf` is present on node4?

 

[AKA]

Hi,
If node1 to node4 are already in the same cluster, the configs in /etc/pve will not change, since it's a synced directory throughout the cluster.
It doesn't matter if ceph is installed on node4 or not.

It will not overwrite any data or create a new pool if you install CEPH on node4 via GUI. It will take the existing config.

But the question is, why no you want node4 to have ceph installed?
I mean it doesn't really matter, for consistency throughout the cluster it might be nice, but as long as you're not planning on adding another mon, manager or metadata servers (Don't know if that's possible in your setup, since i don't know the config and network infrastructure) the only
thing you can do after node4 has ceph installed is to click on node4 in the Web-UI and then on CEPH to see stats and information about the ceph cluster from node4's perspective. But you already can do that on node1 to 3.