qmail and smtproutes
 

We've followed QMR's instructions on how to setup Qmail, and we've got two servers - one for incoming (mail.domain.com) and one for secure smtp (secure.domain.com). We recently deployed the secure smtp server and found one glaring problem with our setup - it retains all email sent to domain.com. So, if you send an email from joe@domain.com to bob@domain.com, instead of forwarding that to the mail.domain.com server, it keeps it locally. I did some quick research and it seems that two things needed to be done:

1.) Clear out the contents of /var/qmail/control/locals
2.) Add ':mail.domain.com' to /var/qmail/control/smptroutes

I've done so, made sure the correct permissions were on the newly created smtproutes file and I've rebooted the server (just in case). At this point, it still retains local email. Is there something else that I can check? I've been reading 'The qmail Handbook' and searching google relentlessly. I did a quick check via /var/qmail/bin/qmail-showctl and it does show

smtproutes:
SMTP route: :mail.domain.com

Success! It turns out that we had our domain listed in /var/qmail/control/virtualdomains, that was causing the local delivery. We're quite happy with the way the system is working now, hopefully that helps someone else in the future.