Reaching Quorum in Proxmox with an External QDevice

Having only two nodes in my Proxmox cluster, I wanted to add a third external device to keep quorum during reboots or other outages. To do so I added an external qdevice as a node which works as a voting only member of the cluster. The qdevice has to be debian based, so I set mine up on a raspberry pi.

First you’ll need to install the following packages on your external server.

sudo apt install corosync-qnetd corosync-qdevice

Once the install is complete, use this command to install a package on each of your existing Proxmox nodes.

apt install corosync-qdevice

Now you can run the following on one of your Proxmox nodes.

pvecm qdevice setup <QDEVICE-IP>

You will need to have a root password available for the setup. In my case I temporarily allowed root login with password and then reverted it back to prohibit-password after. That configuration is found in:

sudo nano /etc/ssh/sshd_config

Once you’ve run the setup command, you’ll be able to run the following to view the status and nodes.

pvecm status
pvecm nodes

For additional information, check out the documentation here.