On Wed, 06 Oct 2010 21:42:57 -0700, Chris Hobbs <cho...@nhusd.k12.ca.us> wrote: > For documentation's sake, here's what I've done so far: > > I do have one more idea I'll throw out there. Everything I've got > here is virtual. I only have the one Dovecot/Postfix server running > now, and the impression I get from you all is that that should be > adequate for my load. What would the collective opinion be of simply > removing the NFS server altogether and mounting the virtual disk > holding my messages directly to the dovecot server? I give up the > ability to have a failover dovecot/postfix server, which was my > motivation for using NFS in the first place, but a usable system > probably trumps a redundant one. > > Chris >
I have done some tests here that shows that NFS is a major overhead compared to local filesystem on iSCSI volume. I have tested only NFS4 with linux clients and server. Finally we went with a couple of mails servers that mount OCFS2 shared volume - this setup also has some drawbacks in terms of complexity. You also could achieve redundant mail system with local fs (XFS for example) over iSCSI volume - one server will be standby and will mount the volume and bring up a floating IP if primary goes down. You could automate such a setup with heartbeat/pacemaker or other cluster manager. Though, in such a setup you could not load-balance if you are serving only one mail-domain. Best regards -- Luben Karavelov Research and development Spectrum Net JSC 36, D-r G. M. Dimitrov Blvd. 1797 Sofia Mobile: +359 884332840 url: www.spnet.net
