Remove Proxmox Cluster

Change Cluster expected number

pvecm expected 1
service pve-cluster restart

Remove master node

systemctl stop pve-cluster
systemctl stop corosync

pmxcfs -l

rm /etc/pve/corosync.conf
rm /etc/corosync/*
rm -rf /var/lib/pve-cluster/*

killall pmxcfs
systemctl start pve-cluster