I'm using Redhat Linux 9.0 - with POSTFIX. I'm certainly not a Linux GURU.
My system is correctly setup and I can send and receive emails (from/to outside world)
I would like to set up my postfix to EXCLUSIVELY use an outside server for sending mail (SMTP)
All client applications would send mails to my server, just as usual, and Postfix would relay them
using the outside SMTP server ...
My EXTERNAL smtp server requires authentication with user/pass.
Which config files do I need to update? Please, provide max details, if required.