I have ISPConfig 3 on a Ubuntu 8.04 LTS server and it all seems to work quite allright but now I run into a problem regarding postfix/smtp relay.
I would like to be able to use the server as an SMTP server that can relay mail to other mail servers. Of course I do not want an open relay so I would like to use authentication.
The problem is: when I specify no username and password, I get a message 'Relay not accepted' which seems fine, but when I do specify a username and password it does not accept it.
Is this functionality set up by default or do I need to change anything in the configuration? And what username/password should I use anyway? The client username/password for accessing the ISPConfig interface or a mailboxname, and if the latter, with or without the domain?
So, lets say my account in the ISPconfig interface is tvdwal, my email address is firstname.lastname@example.org
, which should I use?