How do I configure postfix master to forward all email to an email server ?
 

Let's say I have 2 machines in my network (sitting behind a firewall):

1. An email server (serves x.y@mycompany.com)
2. A SLES (SuSE Linux Enterprise server) server.

I have an application running on the SLES that sends email. The app uses postfix master to send email.

Currently, if my app sends an email to x.y@mycompany.com, the mail is successfully delivered via the email server.

However, if my app sends an email to x.y@yahoo.com, postfix/smtp complains that the mail.yahoo.com is unreachable. I have opened up the firewall so that my SLES server can send email out to the outside world on port 25.

Does anybody know I can configure postfix master so that *ALL* email is sent (or relayed) via my email server?

Thanks in advance.

This is now fixed. I changed my default gateway on the SLES server to point to the firewall. Now, the email server can find all domains (e.g. mycompany.com, yahoo.com, etc)