[PVE-User] Proxmox on DRBD and OCFS2/GFS

[Eneko Lacunza]

Hi Patryk,

On 29/08/13 08:19, Patryk Benderz wrote:
> Dnia 2013-08-28, śro o godzinie 11:13 -0500, Erick Zozoaga Gómez pisze:
>> Hello,
>>
>> We still have three clusters running the old v1.9 with OCFS2 (although
>> it was never recommended by Proxmox):
>>        * One small two-nodes with DRBD Primary/Primary and OCFS2on top.
>>          Never had any problems.
> [cut]
> I have the same setup, and also didn't have any problems. I wonder what
> Martin was referring to, when saying about "problems". It is great
> solution if you want to use older servers, but can't invest in shared
> storage.
I don't know about Martin's experience, but ours was the following:

- Fencing was not correctly setup. I think we were using fencing_manual 
or something like that.
- This caused problems each time servers had to be rebooted (for example 
for a kernel update). If both servers were shut down (server rack was 
moved), then we where unable to recover the block RAID and had to choose 
one of the copies, if I recall correctly.

So we had problems both with filesystem fencing (GFS) and DRBD itself. 
It's very possible it was our fault setting it up, I'm not saying it's 
not possible to get it right! But the benefits weren't worth the 
complexity we found in our setup.

Active-Passive is more manageable as you don't need a cluster 
filesystem, and it's always clear what copy of DRBD is the master copy :)

Anyway lately I think that using iSCSI with MD RAID1 (local disk + iscsi 
disk) is "simpler" than DRBD in Primary/Secondary setup.

Cheers
Eneko

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