[photo] Mark Jeftovic

easyDNS CEO, Career Contrarian & AntiGuru

Enabling SASL authentication on postifx for outbound email

There are a lot of articles about how to enable your postfix server to accept inbound SASL connections for authenticated mail. Sometimes you want to do the opposite: get postfix to route all outbound mail via an upstream mail relay with SASL authentication.

Case in point: Last night I grabbed a new VPS via Slicehost, and there are a few wobbles, but so far the support seems responsive and I loved the lighning fast activation. Who knows what the last occupant of my IP there did though, cause it’s listed in the spamhaus xbl-sbl:

Nov 4 00:43:25 thirteen postfix/smtp[12557]: 7427014027F: to=, relay=smtp.easydns.com[]:25, delay=0.81, delays=0.15/0.01/0.53/0.12, dsn=5.7.1, status=bounced (host smtp.easydns.com[] said: 550 5.7.1 Service unavailable; Client host [] blocked using sbl-xbl.easydns.com; http://www.spamhaus.org/query/bl?ip= (in reply to RCPT TO command))


Well with the increasing popularity of cloud computing and grids, odds are the IP address you’re using now is a bit tarnished. All the more reason to have a stable, dedicated outbound SMTP mailhop setup somewhere. As it happens, I own a company that offers outbound SMTP relaying 🙂 so the next step was just to figure out how to get postfix to do it.

Thanks to “anothersysdmin’s” Postfix as relay to a SMTP requiring authentication, I was able to get it working in about a minute-and-a-half.

Real Time Analytics