Re: [cobalt-users] Two email servers for one domain

[Jeff Lasman <jblists@xxxxxxxxxxxxx>]

Zhang Shiping wrote:

> I have a domain (mydomain.com) hosted by my RaQ 4 but
> email is hosted by another Linux email server. Is it
> possible to have two Linux email servers so if on one
> email server cannot find a user's email account it
> will
> look for the email account on another server?

Anything is possible, Stanley, even striking a match on a wet cake of
soap.

But I'm not sure what you're trying to do.

Are you trying to deliver email to say, an email box on one server, but
if that server isn't available, deliver it to another email box on
another server?  That scenario means your user has to check two
servers.  If your first server is down often enough to make it
unreliable, then the email should always go to the second server, at
least in any scenario I can think of; why bother pointing to an
unreliable server?

Or is your server located somewhere with extremely poor connectivity? 
Don't forget that unless you've got redundant secondary DNS, if your
primary mailserver is down your DNS may also be down.  I'd look for the
problem and try to fix it.

That said, you simply create two  MX records, one pointing to each
server, with a higher priority for the one you want email to try first.

Then, on each server you make sure the server is configured to accept
mail for that domain, and also that you've got configured users and
mailboxes for all the users on that domain.

More likely you'll want a "backup" MX; that is a server that simply
holds email and caches it until your primary email server is back
online.  That's easy, too <smile>.

Jeff
-- 
Jeff Lasman <jblists@xxxxxxxxxxxxx>
Linux and Cobalt/Sun/RaQ Consulting
nobaloney.net, P. O. Box 52672, Riverside, CA  92517
voice: +1 909 778-9980  *  fax: +1 909 548-9484