Ceph Cluster with mixed nodes

[chrisj2020]

Hi folks,

I'm going to build a homelab setup, I want to build this as a Proxmox Ceph cluster, but my budget only stretches to 2 compute nodes. I know the ceph cluster needs a minimum of three nodes to avoid split brain. I'll building two Ryzen 5 based nodes, with 10GB NICs and 64GB of RAM.

Is there a way I can add a third node which only runs the management components for master election decisions? I have an old HP Microserver which doesn't have 10GB Nics, only 8GB of RAM but does have the needed storage built in. It already runs Proxmox and could be re-formatted to be this third node, I just don't want it to try and run my VMs or Containers.

Thanks,
Chris

 

[Alwin]

If you are using HA, then you will definitely need three nodes. See the link for a qdevice (arbiter).
https://pve.proxmox.com/pve-docs/pve-admin-guide.html#_corosync_external_vote_support

But the above has nothing to do with Ceph. For Ceph you will always need three nodes for the MONs quorum. Ever thought about ZFS + storage replication?
https://pve.proxmox.com/pve-docs/pve-admin-guide.html#chapter_pvesr