proxmox add a node to cluster with vm’s on it already

on the new node take a backup of /etc/pve/nodes/YOURNEWNODENAME/qemu-server and delete all the files in it and try to join the server once done restore the file to original location, it worked for me!

  1. NewNode: cp -rpf /etc/pve/nodes/YOURNEWNODENAME/qemu-server /root/
  2. NewNode: rm -rf /etc/pve/nodes/YOURNEWNODENAME/qemu-server/*
  3. OldNode: get the “Join Information” from your main
  4. NewNode: click on “Join Cluster” and add the info copied earlier and join the cluster
  5. NewNode: cp -rpf /root/qemu-server /etc/pve/nodes/YOURNEWNODENAME/

and you are done! just Make sure you have no conflicting VM / LXC IDs.