Click to See Complete Forum and Search --> : Qmail as a backup mx server


Chase
12-02-2001, 02:29 AM
I've finally got a box all setup and running slackware linux 8.0. Killed off all the daemons other than ssh, and installed qmail and got it all running right.

This server's hostname is titanium.chased.org, and has a priority of 20 in my dns (10 is my main mail server, krypton.chased.org).

I know that to make qmail function as a backup mx server only, all you have to do is insert the domains in rcpthosts and not anywhere else (locals or virtualdomains), and qmail will automatically handle the rest by periodically trying to send messages to the higher priority mail server listed in dns for the domain.

My question is, does anyone see a problem with just adding '.' to rcpthosts on the backup mx box? That's a wildcard, so it would recieve email @anydomain. I like this becuase I'm adding and deleting domains all the time, and I would like to only have to edit rcpthosts on the main machine, and just not touch the backup.

I can't think of any problems with this, becuase the backup machine would enqueue all messages sent to it, regardless of domain, and then when the main server comes back up, it will send all the messages there. Then, if a domain isn't listed in the main server's rcpthosts, it will bounce the message.

Any issues with that?

freebsd
12-02-2001, 06:43 AM
>> does anyone see a problem with just adding '.' to rcpthosts on the backup mx box?

BIG problem. Your backup qmail server becomes open relay. Keep in mind, when rcpthosts file is not present, qmail-smtpd will accept ALL messages destined for ANY recipient, including remote hosts. That's why RELAYCLIENT environment variable overrides rcpthosts file.

BTW, putting .chased.org in rcpthosts is very common configuration.

Chase
12-02-2001, 10:33 PM
Ah, yes, that is a big problem, thanks. :)

What do you mean by .chased.org in my rcpthosts is a very common configuration? That's what I currently do for my main box..

chased.org
.chased.org

freebsd
12-03-2001, 04:00 AM
>> That's what I currently do for my main box

Then it's fine.