Autoresponding works only for local email addresses (sendmail and vacatoin)

I have sendmail running on Red Hat, and have set up the program vacation to enable autoresponding to users. For some reason, vacation autoresponds only to local users. For instance, when vacation is set up for, if sends a message to user1, then user2 does get the configured autoresponse message. If sends a message to, he does not get an autoresponse.

Please note that the mailserver is sitting behind a firewall. The IP of is obviously that of the firewall which forwards connections to mail ports to the mail server.

Thank you for the help.
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Karl Heinz KremerConnect With a Mentor Commented:
The log entry only says that the vacation program was called. It does not list an outgoing message. Look at the entries right after the one you quoted.

Why did you think that autoresponding for local addresses was working? What changed your mind?
asa44mAuthor Commented:
BTW, my .forward file contains the following:

|"/usr/bin/vacation -a user1"
Is the box you're doing the vacation on your mail server ?

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Karl Heinz KremerCommented:
Check your mail logs to see if the vacation program tries to send an email.
asa44mAuthor Commented:
- Yes, the vacation program and sendmail are both on the same box.

- This entry from the maillog seems to suggest that a message was sent, but nothing actually arrives:

Apr  4 16:27:20 servername sendmail[5364]: i34FRKYI005363: to=|"/usr/bin/vacation -a user1", ctladdr=<> (519/12), delay=00:00:00, xdelay=00:00:00, mailer=prog, pri=61541, dsn=2.0.0, stat=Sent

I am not actually now sure whether autoresponding for local addresses is actually working.

Stupid question, but is this server able to send emails outside at all ?

Can you try and send an email from the command line (like : mail user@domain.tld) ?

asa44mAuthor Commented:
OK, I have found the problem. A very stupid one. It seems that after I set up vacation and tested it successfully I had  somehow messed up my /etc/hosts inadvertently (I do not know why I opened it). The problem was not that vacation worked for local but not external users, as I thought, but that it had stopped working all together because of the typo in /etc/hosts.

I am giving the points to Khkremer because it was his advice to check the maillog that ultimately alerted me to the problem. Thank you to all of you.
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