Convert Proxmox Cluster Node to Standalone PVE
When adding the Proxmox node into existing cluster, the IP to DNS reverse lookup has different name, miss configuration. Then the new node thought it is already a member of cluster, but other nodes are not.
Convert the node back to local mode
Convert the node
pve-cluster services on the node:
systemctl stop pve-cluster systemctl stop corosync
Start the cluster file system again in local mode:
corosync configuration files:
rm /etc/pve/corosync.conf rm -r /etc/corosync/*
Start the file system again as a normal service:
killall pmxcfs systemctl start pve-cluster
The node is now separated from the cluster.
Remove the node from cluster
Deleted it from any remaining node of the cluster if it is already a node of cluster
pvecm delnode oldnode
If the command fails due to a loss of quorum in the remaining node, you can set the expected votes to 1 as a workaround:
pvecm expected 1
And then repeat the pvecm delnode command.
Cleanup the cluster files
This ensures that the node can be added to another cluster again without problems.
/etc/pve/nodes/<node_name> from other nodes.
Stop remove access
Remove ssh key from /etc/pve/priv/authorized_keys file