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nunder
05-22-2001, 04:23 PM
Well, I'm not even sure that I'm typing this qq right, but, here goes:

I've got a RH Linux box running my firewall. I've setup logical interfaces on the external interface for my HTTP, and SMTP server. I've also setup MASQ rules (ipmasqadm portfw -a -P tcp -L <logical address> <port num> -R <internal address> <port num> ) to pass the traffic to the appropriate server. Some mail is still getting bounced. When I do a sendmail -v -q, I can see the remote mail server talking to the firewall, instead of the logical IP of the mail server. Then, it says "Domain of sender address username@network.com does not resolve". I can finger the user on the mail server, and get the information, I can do an nslookup for the mx record for my domain, and it resolves properly, I can then do an nslookup for the mail server, which resolves properly, and I can telnet from an outside machine to port 25 of the mail server, and the appropriate mailserver responds. Any ideas?

nunder
05-22-2001, 04:35 PM
Heres the 'conversation', if it helps. The names have been removed to protect the innocent.
221 2.0.0 mailserver.theirdomain.net closing connection
220 mailserver.theirdomain.net ESMTP Sendmail 8.11.0/8.11.0; Tue, 22 May 2001 16:33:54 -0400
>>> EHLO mymailserver.mydomain.com
250-mailserver.theirdomain.net Hello [myfwip], pleased to meet you
250-ENHANCEDSTATUSCODES
250-8BITMIME
250-SIZE 10240000
250-DSN
250-ONEX
250-XUSR
250 HELP
>>> MAIL From:<myuser@mydomain.com> SIZE=28059
451 4.1.8 <myuser@mydomain.com>... Domain of sender address myuser@mydomain.com does not resolve
<remoteaddress@theirdomain.net>... Connecting to mailserver.theirdomain.net via esmtp...
<remoteaddress@theirdomain.net>... Closing connection to mailserver.theirdomain.net.
>>> QUIT

[ 22 May 2001: Message edited by: nunder ]