[OpenAFS] Using OpenAFS for implementing mail servers

[Russ Allbery]

Jatin Nansi <linuxguru@india.com> writes:

> we are planning to implement a clustered mail server, having upto 4
> physical servers providing mail (smtp, pop3) and web mail (http) to our
> users. for this we need to keep the filesystems synchronised amongst all
> the machines, as the user may land up at any server, and his data better
> be there at that server. the clusetering solution would be something
> similar to piranha or turbocluster. this is a round robin load balancing
> solution. all servers are expected to perform high file i/o.

> since the volume of the mail is very high at our site, typically upto a
> GB a day, is it possible for me to use openafs for keeping all the
> servers synced,

I've yet to hear from someone who's had good experiences doing high-volume
mail into AFS.  It's possible to deliver mail into AFS, but it's very slow
according to everyone I know who's tried it.  You run into a few problems;
locking inside AFS isn't something you generally want to use.  The write
performance is also pretty annoying.

> if not what else can i use for this purpose?

Probably the most common solution that I've seen for this particular
problem is to put the mail on a NetApp machine or something equivalent and
then make sure that it and all your servers speak the same variety of NFS
locking.  We take a different approach and assign each user to one and
only one POP server, but use DNS to give them names of the form
username.pobox.stanford.edu so that we can move things between POP servers
if necessary.

-- 
Russ Allbery (rra@stanford.edu)             <http://www.eyrie.org/~eagle/>