suggestion need to design an email system.

[Jens Hoffrichter]

Hello,

2008/9/17 Simon Matter <simon.matter at invoca.ch>:
>> Another thing which really intrigued me was the inherent
>> cluster-ability of dovecot, which is a huge PITA to get to run on
>> cyrus (as I have just implemented it a couple of months ago). Yet I
>> only have read about it in the documentation, and not actually seen it
>> in action. But at least they thought about running on a clustered file
>> system........
> Cyrus works quite well on a cluster with clustered filesystem. Do you talk
> about murder/replication or a 'simple' cluster?
Sorry, I really didn't make myself clear here.

I'm not talking about an active/passive cluster, where one cyrus
instance is running and another server takes over when the main one
dies, but an active/active configuration, where several nodes access
the same meta databases and mailboxes which is residing on a SAN with
a clustered filesystem (in my case GFS).

And cyrus had some issues running in that configuration which took us
a week or two to figure out, which were related to the berkeley db
support compiled in. There are some things regarding mmap file io, GFS
and mutexes which doesn't really work. After I compiled cyrus without
bdb support, it now works like a charm, and we have now 5k mailboxes
on the 3 machine cluster, testing it now for a couple of weeks before
we migrate the rest of the mailboxes :)

Dovecot seemed to have thought and adresses those issues about
concurrent access, and it just seems to play more nicely in a
heterogenous environment than cyrus, which needs exclusive management
access to the mailstore. At least, if you follow best practices, and
everything else is a bit of a guessing game.....Been there, done that
;)

Jens