When I started work this past month, my first task was setting up a VPS for the website that will provide other services as well (SVN, mail, etc). Setting up a LAMP server isn't that difficult for me, but I've been totally flummoxed by Sendmail/Postfix/EXIM4.
I'll explain what I've done, and what isn't working. I set up a Ubuntu 10.04 VPS with VPS.net, and use ISPManager to configure many of the services. I set up sendmail initially, but that didn't seem to work, so I moved to POSTFIX which appears to be working better. The server is directly connected to the internet, so I don't want to relay mail anywhere but my system. It seems I can send messages locally without many problems, but I can't get external messages. According to mail.log, messages are queued, and I see the from/to addresses, but doesn't seem to be delivered.
Is there anyone who knows a lot about postfix and Linux configurations that might help? What else should I look at?