I am planning a proxmox HA configuration with two Dell R710 machines (dual 6 core processors in each) with enterprise level drive raid arrays. I would be using DRBD with a quorum disk on a third machine. I would dedicate two 1GB nics on each server to the DRBD communications. We would have approximately 12 to 14 Virtual Machines running on this pair of servers. The proxmox manual recommends creating two DRBD resources - one for the Virtual Machines that normally run on ServerA and one for the Virtual Machines that normally run on ServerB. This is because of the Primary/Primary state in which this configuration runs. If both servers have VMs talking to the same DRBD resource and a split brain situation occurs, there is potential for data corruption that must be resolved.

While I understand it would take more effort to create new virtual machines, can anybody foresee any potential problems with running a separate DRBD resource for each VM instead? Does anyone have experience running a setup that way and has it worked well? It seems to me that would allow more flexibility in moving machines back and forth.