Mail Servers in OS X: potential problems
Mail Servers in OS X: potential problems
AppleMailServer is the default. It has similar features to the mail server found in ASIP. However there is no way of setting the server to not operate as an open relay without turning off all incoming and outgoing mail. This makes it dangerous to install on any machine which is accessible from the internet, even with a firewall in place. [For further information about the dangers of running an open relay, see this site.]
Less serious but still annoying: The only way to alias an email address (for example, point info@domain to fred@domain) is to create another user on the system, forward their mail and disable the user. And, although promoted as supporting multiple domains AppleMailServer does not differentiate between fred@domainone and fred@domaintwo. There is no way to route these to separate users.
The other MTA bundled with OSXS10.0 is Sendmail. It does not suffer from this problems above, but its config files as shipped with OS X Server10.0 have the wrong permissions, preventing Sendmail from working.
Sendmail and Postfix Tom Cheney writes of a possibly related problem with Sendmail in OS X 10.0.4: "I'm using OS X to run a web server. After updating to 10.0.4, sendmail seems to have broken. After running the gamut of the usual routines, checking directory permissions, updating config files, etc., I finally gave up. I installed Postfix and mail services are available again."
A further message from Tom provides more details:
"It was a few days after I updated OS X that I realized there was a problem. Monday's mailing list wasn't being sent out, so I tried to do it manually only to get writable directory errors:
WARNING: writable directory /etc
WARNING: writable directory /var/spool/mqueue
I've seen this before on new installations of sendmail, so I performed the usual routines to make sure the all the directories had the correct permissions.
After a couple of hours, sendmail would still hang on initialization, so I gave up and installed Postfix (an open-source alternative to sendmail). Stepwise has an excellent walk-through on installing postfix and all the libraries it needs. For those that aren't as comfortable downloading and installing all the libraries, The Huntsville Macintosh Users Group has a script to perform the task for you."