sendmail error: user unknown dsn=5.1.1
 

I recently was able to get sendmail working on our Debian server. However, there is a small problem. I can send email to:

jsmith@DOMAIN

but NOT to:

jsmith@DOMAIN.com

I get this error: stat=User unknown and dsn=5.1.1 in /var/log/mail.log

We also have an alias domain (jsmith@ALTDOMAIN.com) that works fine.

How can I get jsmith@DOMAIN.com to work? Thanks!!

It sounds lkie you have DOMAIN.com set up but there is no mailbox record for jsmith@DOMAIN.COM, more than likely has yuor main account as jsmith@DOMAIN.

Try setting jsmith@DOMAIN.COM as a virtual mailbox.

/etc/mail/local-host-names < Make sure DOMAIN.COM is listed on this file



/etc/mail/virtualusertable

Add:

I tried that but it didn't work the way I was hoping. Here is our configuration:

computer 1
Debian Linux with sendmail

computer 2
MS Server with Exchange
DOMAIN.COM

When we send email from computer 1, it goes to computer 2 (the smart host). However, if the email address we use is jsmith@DOMAIN.COM, it sends it to computer 1. I saw the test email in /var/mail/jsmith.

How can we get it to send from computer 1 to computer 2 while specifying DOMAIN.COM?

Thanks!

Remove domain.com from /etc/mail/local-host-names

Looks like that fixed it, thank you!!!

It helped me as well as it seems. Thank you very much.
I was getting the following in /var/log/maillog

Jan 16 15:50:00 host sendmail[4059]: s0GHo08d004059: <email@domain.com>... User unknown
Jan 16 15:50:00 host sendmail[4042]: s0GHo0Ei004042: to=<email@domain.com>, ctladdr=noreply@domain2.com (503/501), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=67453, relay=[127.0.0.1] [127.0.0.1], dsn=5.1.1, stat=User unknown