Postfix - SASL_auth and relay for specific IP

Hi All

… the solution is probably staring me in the eye somewhere, but I have googled for a few hours without finding it.

I have a webmin/postfix server set up. Postfix used sasl_auth for user authendication. I have one company which uses this server for outgoing email, who want to send email directly from their accounts software and from what I gather there is not an option for this authendication within the accounts software. They are on a fixed IP, so I thought adding their IP address to mynetworks (In postfix ‘General Options’ I set 'Local Networks to ‘’.

The result of this was that my other users could no longer log in. Any idea how to achieve what I am trying to do? Any help is much appreciated.<br><br>Post edited by: OnTheRoadInWales, at: 2009/05/27 03:21

Well, first off, I’ll offer that very few email clients lack an email authentication feature.

A large number of ISP’s are requiring authentication – and that’d be really bad if clients didn’t support it :slight_smile:

But, you should be able to add a new IP address, or IP range, to the mynetworks setting.

You can either add something like if it’s a single IP, or if it’s a range of IP’s.

Adding a new IP shouldn’t break things for existing users unless perhaps there was a syntax error relating to that line.

If you try adding the IP again, you might want to look in the email log (/var/log/maillog or /var/log/mail.log) to see if there are any errors.

You could also try manually adding it to mynetworks by logging in over SSH, and editing /etc/postfix/