On Thu, August 2, 2007 3:06 pm, John fistack <[EMAIL PROTECTED]> said:

> I know webmail.us use Dovecot, what is the most big dovecot architecture 
> known ?
> Do you think Dovecot can handle 1 million of active users in a good 
> architecture ?

Yep... and we have 500K very active users on it.  We've scaled Dovecot 
horizontally without NFS, just lots of independent Dovecot server intances with 
smart proxy/mail-routing infrastructure around it.  It can easily scale to 
millions of users this way.  Just make sure you throw enough disks at it and 
you'll be fine, with or without NFS.

> Do you think it's a good solution to use one synchronised local Openldap on 
> each
> server Dovecot ?

No.  I'd replicate your ldap database on a few servers that are dedicated to 
that purpose, and on each mail server use Dovecot's auth_cach feature to 
minimize how often it needs to query ldap.
 
> Do you think It's possible to use Postgresql or MySQL instead of Openldap ?

We use MySQL.  MySQL handles frequent writes better than OpenLDAP from our 
experience.  It is also simpler for us to do replication and troubleshooting 
because we employ several MysQL gurus already.

> Are cyrus or courrier-imap better solutions ?

Definitely not courier-imap, because of it's lack of indexes.  Not sure about 
Cyrus.

> Someone say "Zimbra is highly scalable and fast", I think Zimbra could be to 
> heavy
> in this architecture, is Dovecot scalable ?

My opinion is Zimbra is too heavy beccause of the way mail is stored on the 
backend.  Dovecot with maildir scales out well, and the promise of dbox mail 
storage format appears that it will make it even more scalable down the road.

Bill


Reply via email to