CentOS Sendmail – Ignoring MX Records for Local Domain

centossendmail

I have set up my domain to use google apps for its mail server. I have set up the appropriate MX entries in DNS. Any mail sent from the server to outside mail works fine. The problem is when I am sending mail to users on my domain. For example mail to "me@example.com" will go to my local mailbox for user "me", instead of checking the MX record for example.com and going to gmail.

I have searched google for hours and found people with this same problem, I haven't found any solutions yet though.

EDIT:
For the record, I have DontProbeInterfaces set to true and I don't have the my domain in Class w

Best Answer

Some people in #sendmail on freenode helped me figure out that the problem in this particular case was not with send mail, but my dns records. I had a CNAME for my domain name pointing to the application server that was sending the mail, using an A record instead fixed the problem.

Related Solutions

Centos – Disable local delivery in Sendmail

What I did to disable local delivery. I'll be using the example.com domain.

Requirements:

example.com A entry pointing to IP address assigned to one of the eth interfaces.
/etc/hosts defining example.com assigned to the very same IP address as above
example.com MX records pointing to Google servers (ASPMX.L.GOOGLE.COM, etc)
default sendmail installation (mine was on Ubuntu)

Steps:

vim /etc/mail/sendmail.mc

at the end:

define(`MAIL_HUB', `example.com.')dnl
define(`LOCAL_RELAY', `example.com.')dnl

and then:

sendmailconfig (or /etc/mail/make depending on your distro)
service sendmail restart

testing:

echo -e "To: user@example.com\nSubject: Test\nTest\n" | sendmail -bm -t -v
echo -e "To: user\nSubject: Test\nTest\n" | sendmail -bm -t -v

You should see it connecting to the google server and then you should see your mail being delivered to your Google inbox.

Sendmail to Local Domain Ignoring MX Records – Part 2