On Mon, Jan 27, 2014 at 02:38:01PM -0800, Quanah Gibson-Mount wrote:
> >>Actually, that is not too difficult. Just specify a round-robin
> >>name as the "lmtp_fallback_relay" (new feature). While adding SRV
> >>support is tricky, adding "lmtp_fallback_relay" is I think quite
> >>simple.
> >
> >That would be cool. We store all the servers in LDAP, and use LDAP to
> >look up the target mailstore for a user now, so we could have the default
> >LMTP use the LDAP lookup for their primary store, and then use the
> >fallback relay do a LDAP lookup that returns a list of the other servers
> >if that one is down.
The fallback relay setting is a fixed per-transport setting. So
the fallback relay would not be per-user. Only the first LMTP
server to try (per-user transport table). Each transport carries
a fixed fallback relay in master.cf.
So you'd have one transport per "cluster" of mailstores, and an
associated fallback that uses the clust round-robin address. The
user's transport entry would direct the first delivery attempt to
"somelmtp:primary-store:port" if it is best to not simply round-robin
the deliveries and sending each user's mail to the primary destination
for that user is substantially better.
--
Viktor.
