sending mail from a DMZ

[dendenners]

Hi,
I've a linux (Redhat 8) machine on a DMZ. I want to SEND email only from this machine (only to address within our own LAN) and no email has to be received. However, when I try to send email, the following type of error is cropping up in the /var/log/maillog: (the names of the machines have been changed to protect the innocent)


Apr 2 15:06:20 dmzmachine sendmail[5466]: h32E60l7005466: from=<root@dmzmachine.foo.bar>, size=264, class=0, nrcpts=1, msgid=<Pine.LNX.4.44.0304021505480.5253-100000@dmzmachine.foo.bar>, proto=ESMTP, relay=root@localhost
Apr 2 15:06:24 dmzmachine sendmail[4882]: h32E2iEF004877: to=<mailuser@foo.bar>, ctladdr=<mailsender@dmzmachine.foo.bar> (500/100), delay=00:03:20, xdelay=00:03:20, mailer=relay, pri=30270, relay=dmzmachine.foo.bar. [123.456.7.8], dsn=4.0.0, stat=Deferred: Connection timed out with dmzmachine.foo.bar.


I think I need to tell the machine how to relay mail, but I don't know how exactly to go about doing this. I know the IP address of a mail server that I can use, and that address is pingable. How do I tell my machine to relay all non-local mail to this machine? Would I also be right that I don't need the full-blown sendmail daemon runnig on my box to send mail (I don't want that hassle just to send email)
Thanks
Denis

 

[dbase77]

HI,

Do you have main mail server? Config smarthost within sendmail.cf file. This smarthost is your main mail server who is going to send/receive mail within our LAN. Make sure your Main mail server relay your domain.

regards,
feroz