[Dovecot] [OT] DRBD

[alex handle]

On Mon, Nov 23, 2009 at 10:25 PM, Rodolfo Gonzalez Gonzalez
<rgonzalez at gnt.cc> wrote:
> Hello all,
>
> has someone worked with DRBD (http://www.drbd.org) for HA of mail storage?
> if so, does it have stability issues? comments and experiences are thanked
> :)
>
> Thanks,
> Rodolfo.
>

We have deployed active/passive DRBD Mailserver for a customer with ~
5000 mailboxes.
runs nice without any problems.

CentOS 5.3
Heartbeat 1 !
DRBD 8.3.x
LVM

If you try to use LVM/ext3 with DRBD and you want to use consistend
snapshots, use this setup

http://www.drbd.org/users-guide-emb/s-lvm-drbd-as-pv.html

Storage layer:

disks/hwraid/softwareraid -> drbd -> LVM -> fs

this way lvm can trigger the fs with a freezecall before the
blocklevel snapshot.


We currently migrate our 10000 Mailcluster from a netapp storage to
multiple storage server with drbd.

Our other project the webcluster runs with about 1000 sites
(Typo3/Joomla) on a CentOS nfs-server backed with the drbd.
The failover time is about 4 seconds and no pending write ist lost.