Quoting Tomek timor@o2.pl:
For now I don't know how to "glue" these severs:
- if I should install dovecot on both postfix and use third servers as a NFS share?
This will work, but doesn't scale well and performance problems may be hard to pinpoint. You have to be very careful when using NFS like this, but it is possible and fairly easy conceptually.
- or maybe it is possible to communicate with dovecot on third server via LMTP?
No idea... You could surely configure the two postfix machines to deliver to the dovecot server via LMTP. Very similar to your next version below if used that way.
- or should I run third postfix daemon (without antyspam etc - simple configuration) on the same machine as dovecot only for delivering local mails?
You could do that. Scales better IMHO than option one... I ran this way for years (but don't anymore).
You could also cluster the machines and use a cluster filesystem, but that may be outside your comfort zone.
I will be grateful for any advice, howto or good practices example.
Depends on a lot of factors, so in the end you will have to decide... Good luck with it.
-- Regards, Thomas.
-- Eric Rostetter The Department of Physics The University of Texas at Austin
Go Longhorns!