I am newbie in Ubuntu and Unix in common and I have a question about mail. I did setup sendmail on my server. Emailing to user form php scripts working fine, but in /var/etc/mail.info log I see a lot of lines like this
m-mta: r2NNmR5N007850: to=<email@example.com>, delay=03:08:04, xdelay=00:00:00, mailer=esmtp, pri=1740000, relay=mydomain.com., dsn=4.0.0, stat=Deferred: Connection refused by mydomain.com.
Log files full of this and sendmail repeat sending, because every attempt was fail. My questions is: What is going on? Who send this messages to local users (not only root, www-data too)? How can I stop this?
My Ubuntu 10.04. Thank you and sorry for my bad english