I have been using a Proxmox VE 2.0 cluster (2 servers) for months.

Today, I had the "bright idea" to install a GUI on one of the servers. I used tasksel, and selected the graphical desktop environment (Gnome).

When I rebooted the server, neither of the servers on the cluster could see each other (shows a red light by the server on the sidebar, no statistics). The VMs on each server are working fine, individually.

pvecm status on the broken server shows cman_tool: cannot open connection to cman, is it running ?. Running it on the other server outputs a lot of lines (here: http://pastebin.com/HpQfUHTU), but I assume the important bit is

expected votes:2
total votes: 1

Trying pvecm delnode (othernode) on either server outputs:

cluster not ready - no quorum?

Any suggestions as to how I can fix this? Thanks in advance!