[Linux-cluster] Postfix active/active mail cluster

[Gordan Bobic]

joe digital wrote:
> Hi, We would like to build a postfix & Dovecot active/active mail 
> cluster with a shared data backend (ocfs2 or gfs).  Has anyone done this 
> with or without the use of front end load balancers (done with DNS?).  

Yes, I have deployed just such a thing using Postfix, Dovecot and GFS. I 
set up authentication via a MySQL user database. User maildirs were 
shared on a separate GFS volume, and the root volume was shared between 
all the machines in the cluster (5) using Open Shared Root.

Local storage was used for:
1) /tmp
2) /var/lib/mysql (MySQL was multi-master replicated using round-robin 
replication)
3) postfix incoming mail spool
4) /boot
5) OSR initrd disk backing

Load balancing was done via DNS. The system was based on CentOS 5. 
Storage was SAN for root and maildirs and DAS for the above.

Gordan