Proxmox Cluster

[taich]

Is it possible to add a new proxmox 7 server to a proxmox 6.4 server and form a cluster with this two?
I then want to move the vm's to the new 7 server and remove the old 6.4 server from the cluster.

Or is there a better way to do that?

 

[aaron]

As always, it depends

Two single nodes? Nothing like Ceph or the likes? That could work, though I haven't tested it.

If you can live with a bit of downtime, you could also create backups of the VMs on the old node, make them available on the new one as well (same network share) and restore them. That would most likely be cleaner and less effort (no cluster creation, no destruction of the cluster, ....) but the VMs will have some downtime.

 

[taich]

There is a VM with 8TB data, downtime would be 24 hours or more. So backup is plan B.
I will try this with 2 nodes and post the results here.

Thanks.

 

[spirit]

Is it possible to add a new proxmox 7 server to a proxmox 6.4 server and form a cluster with this two?
I then want to move the vm's to the new 7 server and remove the old 6.4 server from the cluster.

Or is there a better way to do that?

yes, you can mix proxmox6 && proxmox7 in 1 cluster. live migration will work from 6--->7, so you can remove the proxmox6 node later.

 

[taich]

The idea to migrate with a 2 node cluster worked perfectly.
I just want to add some notes I want to mention.

1. Create the cluster on the old machine and then join the new node with no vm or container installed.
2. The ZFS pool has to have the same name on both nodes.
3. The network vmbr has to have the same name on both nodes.
4. You have to know the procedure for a node to leave a cluster.

I found that in Proxmox help. I dont know if there is a better way.

systemctl stop pve-cluster
systemctl stop corosync
pmxcfs -l
rm /etc/pve/corosync.conf
rm -r /etc/corosync/*
killall pmxcfs
systemctl start pve-cluster

 

[aaron]

For other people who come across this, looking to remove a node from a cluster, here is the section in the admin guide: https://pve.proxmox.com/pve-docs/pve-admin-guide.html#pvecm_separate_node_without_reinstall

Having a bit of an explanation and the hints and warnings should be helpful