March 11, 2013

Trying to configure sendmail in Debian

I'm trying to configure sendmail on our Debian Linux server to send mail, using our Exchange server as a relay. I'm a total noob at all of this.

We can send mails to internal addresses (for example, if our domain name is, the server can send mail to [email][/email]) with no problem.

We can't send mail to external addresses like [email][/email] or [email][/email]. Here's an example of what I get in /var/log/mail.log

Mar 7 14:45:29 newton sm-mta[17159]: r27JjOw1017159: to=, ctladdr= (0/0), delay=00:00:05, xdelay=00:00:05, mailer=relay, pri=30455, [], dsn=5.7.1, stat=User unknown

Also, I get this:

root@newton:/etc/mail# sendmail -bv deliverable: mailer relay, host, user

Does that mean the [email][/email] is unknown to newton, or unknown to Exchange?

Is there something in Exchange we need to configure?

I have no idea what to configure. Please help. Thanks!

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