PostFix SMTP Relay

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The Exchange guy came up with a pretty neat solution to an issue we have when dealing with one of our core systems.

This system needs to send emails.  Far enough.  However this system doesn't do authenticated SMTP.  Ok that's not great but many things don't do authenticated SMTP.

The system is installed on client machines.  Err sorry what?  You need client machines to relay through the Exchange environment?

User says: "It worked before we went to Exchange 2010"
Exchange Guy "How?!"
After a few moments of checking the old 2003 Exchange environment...
Exchange Guy "Holy Cow!  All users can open relay!"

Oh great.  o now the business wants business as usual.  IT Team want secure as possible SMTP.  Push you .  Pull me.  We can't allow open relay for various reasons most of which are clearly documented out in the web :)

Exchange Guy "Why not use an SMTP smarthost relay!"

Awesome.  Trouble goes away.

I put in place a Debain box running PostFix, added the IP of the PostFix box to Exchange receive connector, put in place IP restrictions for those clients able to relay and bing...oh.  no.

Little bit of tinkering around and found the issue.  I had typed Relayname not relayname into the config file.  Easy mistake especially as the Debian VI app is pretty nasty to use :)

EHLO!  We are in business again.  The application points to the SMTP server which does the relay.

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