I have a sendmail server that's doing something funny. (Funny to me anyway)
It's on a RHEL box and there is an application on the same box that sends messages. The messages are set to send to (for example)
to: [email protected] [email protected] from: [email protected]
and I don't get any of the emails. I added an external (gmail) account to the CC and get that email ok. Looking at the header on the email that is received, sendmail is changing the addresses to
[email protected] [email protected] and [email protected] respectively.
This is because on our LAN if you ping domain.com, you get back www.domain.com through a CNAME record we have set up. We want any "invalid" addresses typed into IE to take you to our home page... so if you ping asdfasdfasd.domain.com, you'll go to www.domain.com
How can I modify sendmail to not do it's own DNS lookup on our domains? I did a packet capture on the traffic to verify that's what it is doing. A host file on the local machine has no effect, I'm sure I need to tell sendmail to actually USE the hosts file, or someting. Help is appreciated.
What you are asking for is done via the /etc/mail/service.switch file. Its syntax is similar to the nsswitch.conf(5). However, your setup is complex, and flawed if indeed you've used CNAMEs in places you shouldn't have.