Proxmox Certificate Error Fix After Node Replacement

Intro

a while ago, I replaced one the servers for one of the nodes in my 3-node Proxmox cluster. To make the change, I removed the cluster and re-created it using the same name. However, after setting it up again, I started encountering errors when trying to SSH into the cluster or access the console for my VMs and containers.

Through my troubleshooting and research, here’s how you can fix it.

1: Remove all HTTPS Certificates

Open the Shell on the node, For the command update the names per your name convention for each node

rm /etc/pve/priv/pve-root-ca.key
rm /etc/pve/nodes/pmx01/pve-ssl.pem
rm /etc/pve/nodes/pmx02/pve-ssl.pem
rm /etc/pve/nodes/pmx03/pve-ssl.pem
rm /etc/pve/nodes/pmx01/pve-ssl.key
rm /etc/pve/nodes/pmx02/pve-ssl.key
rm /etc/pve/nodes/pmx03/pve-ssl.key
rm /etc/pve/authkey.pub
rm /etc/pve/priv/authkey.key
rm /etc/pve/priv/authorized_keys

2: Generate new HTTPS certificates

pvecm updatecerts -f

3: Restart pvedaemon and pveproxy services

systemctl restart pvedaemon pveproxy

4: Rename SSH Certificates

SSH is used to migrate VM's between nodes.

mv /root/.ssh/known_hosts /root/.ssh/known_hosts_old

5:Reboot

Finally, shutdown the VM's and reboot the hosts, one by one.

Additionally, refresh the web browser page you use to connect to the PVE cluster and accept the new certificate.