topic Sendmail relay and dns lookups in Operating System - Linux

Sendmail relay and dns lookups

Gregory Marchese_1 — Fri, 01 Apr 2005 10:34:10 GMT

Here is the problem. We have a server running HPUX 11.00 and sendmail 8.9.3 we have our DS record set in sendmail.cf to send mail to the exchange relay server. This works for all addresses except ones that can not be found in DNS or /etc/hosts. The result is the message gets deferred and stays in mailq. Is there reason this mail never leaves teh unix server? shouldn't it be treated as any other mail and go off to the relay? Is there something I'm missing in on of teh config files?

Thanks in advance. points will be awarded.

-Greg

Re: Sendmail relay and dns lookups

RAC_1 — Fri, 01 Apr 2005 15:55:24 GMT

This is expected behavior of sendmail. If a addresses can not be resolved, that email will just sit in mailq only.

Re: Sendmail relay and dns lookups

kcpant — Sat, 02 Apr 2005 00:11:11 GMT

Hi Gregory,

You can use a feature (relay_hosts_only) and define your network range in access file for allowed networks. In this way mails will be relayed even if dns/hosts could not be resolved.

Re: Sendmail relay and dns lookups

Gregory Marchese_1 — Mon, 04 Apr 2005 08:25:21 GMT

Thanks guys.

I solved this by commenting out
# pass to name server to make hostname canonical
#R$* < @ $* $~P > $* $: $1 < @ $[ $2 $3 $] > $4

then changing

F=mDFMuX
to
F=0mDFMuX

in section
#####################################
### SMTP Mailer specification ###
#####################################
Msmtp, P=[IPC], F=0mDFMuX, S=11/31, R=21, E=\r\n, L=990,
T=DNS/RFC822/SMTP,
A=IPC $h
Mesmtp, P=[IPC], F=0mDFMuXa, S=11/31, R=21, E=\r\n, L=990,
T=DNS/RFC822/SMTP,
A=IPC $h
Msmtp8, P=[IPC], F=0mDFMuX8, S=11/31, R=21, E=\r\n, L=990,
T=DNS/RFC822/SMTP,
A=IPC $h
Mrelay, P=[IPC], F=0mDFMuXa8, S=11/31, R=61, E=\r\n, L=2040,
T=DNS/RFC822/SMTP,
A=IPC $h