sendmail - DSN: Name Server host not found

Posted by Daniel Mitchell on Server Fault See other posts from Server Fault or by Daniel Mitchell
Published on 2011-10-03T13:47:48Z Indexed on 2013/10/24 15:58 UTC
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unix

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sendmail

I've recently setup a new backup server and have configured sendmail with a smart_relay_host

Except every email from the command line doesn't go anywhere. From mail.log:

Oct 3 14:32:52 **back01 sm-mta[16570]: p93DWqtC016568: to=<.@.com>, ctladdr= (0/0), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=120762, relay=10.2.30.60, dsn=5.1.2, stat=Host unknown (Name server: 10.2.30.60: host not found) Oct 3 14:32:52 ***back01 sm-mta[16570]: p93DWqtC016568: p93DWqtC016570: DSN: Host unknown (Name server: 10.2.30.60: host not found)

DNS is working correctly on this box. I can do forward and reverse lookups.

I can also telnet to the mail relay and send a message that way.

I'm stumped, any suggestions?

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