System Architecture: All/General
RedHat Release: RHL 5.1 (Manhattan)
FAQ Category: Email
Modification Date: Oct 7, 1998
Hi, I've got a Win95 machine that's behind a Redhat 5.1 Linux Masq box. the masq box also runs my mail server. On my Win95 machines I can receive mail from the Linux box just fine, but when I try to send email it says "...address@server.com, we do not relay.
You have run into an anti-SPAM defense. Previous RedHat releases had relaying turned on by default. Spammers would actually search the net for RedHat servers whose admins hadn't turned relaying off and use them to forge mail. To stop this, RedHat now ships with relaying turned off by default. Put the Windows machine's IP address (and the IP addresses of any other machines that will be sending mail) in the /etc/mail/ip-allow file. You can also put names in the name-allow file. Then get sendmail to re-read its config files, easiest is probably issuing a "killall -HUP sendmail" command, hardest would be to reboot the box. You should now be able to relay mail from specific machines through your server.
Thanks to Alexander Woodby