[KLUG Members] Postfix relay_domain question

[Bob Kanaley]

Management has request that I forward company email to a semi-retired
employee's home email account at Yahoo. I am concerned that the only way I
know how to do this will open my SMTP server to Yahoo spammers.

I am running a RedHat 7.0, Postfix 20010228 SMTP server chrooted in a DMZ. I
have about 30 Win98 clients on the company LAN using secure POP3 to pickup
email from that server.

The simplest way that I could figure out to forward his email to Yahoo was
to add his yahoo.com address as an alias in the alias database and add
yahoo.com to my rely_domains in the Postfix main.cf file.

However, from reading the Postfix doc's and searching the Postfix list
archive, I can't figure out if adding yahoo.com to my relay_domains in
Postfix will allow Yahoo spammers to bounce UCE off of my Postfix SMTP
server?

If I knew how to spoof a source address I might be able to test this out for
myself. But, I am hoping there is someone on this list with more Postfix
experience than I have who might know the answer off the top of their head.

If this additon to my relay_domains does allow spamers to bounce email off
my server, I will need to take another approach to forward the employee's
email. I would appreciate any suggestions.

Most of what I have been able to find on email forwarding seems to use
procmail. It seems that procmail with a ~./forward file in the users home
directory on the email server would be a logical way to forward email. But,
I use the Postfix default /var/spool/mail/ directory for the SMTP
destination and for security reasons, I have configured the SMTP server so
that none of the Win98 clients have home directories on the mail server. I
would have to install procmail, create home directories and reconfigure a
working mail server just for one user. I hope there is a simpler way.


Bob Kanaley
IS Manager
Agdia, Inc.