DRBD on RAID

[ely_az]

I have 2 servers with large 12 disk hardware RAID 10 arrays that I want to set up like the DRBD wiki (http://pve.proxmox.com/wiki/DRBD). In that example and most others I have seen the DRBD volumes are always recommended to be on their own physical drive/array and Proxmox or whatever base hypervisor runs on it's own disk. I want to utilize the performance and redundancy of the RAID 10 for both the VMs and Proxmox. Is it okay to use LVM volumes from the RAID disk as backing for the DRBD volumes? I can't find any performance metrics on this setup versus using separate physical devices for the hypervisor and DRBD backing. I could add an SSD to run Proxmox on if the performance would be significantly improved.

 

[udo]

Hi,
depends on your raidcontoller, which config is the best.
I would not recommend DRBD on top of LVM, because of to many layers: block-device -> lvm -> DRBD -> lvm -> VM-disks

In my setups (I use 4 couple of pve-nodes with DRBD - up to some TB in size) I use independ raid-volumes as storage for DRBD. So I can change single drbd-volumes if needed.

Udo