Sendmail Configuration to not deliver mail to local machine

emailsendmail

I have sendmail up and running on an Ubuntu 8.04 machine. It can send mail correctly to all but the domain to which it is a part. How do I configure it to not send to itself for email addresses on its domain? I want it to use the MX records for its own domain just like it does for other domains, so that the email is delivered to the mail server for the domain, not to itself.

Matt

Best Answer

If you are playing the "sendmail.mc" game:

define(`SMART_HOST',`smtp.your.provider')

If you hack sendmail.cf directly:

DSsmtp.your.provider

...but if you hack sendmail.cf directly you probably already knew that.

This tells the system that for accounts in its own domain that it doesn't directly know about, send mail to smtp.your.provider which presumably knows what to do with it. Note that accounts that it does know about (ie root) will need to be aliased to a non-local account or messages to root will be delivered locally.

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 local domain is hosted externally e-mail fails :(

I think you may benefit from "nullclient" configuration of sendmail. Just put the following in your /etc/mail/sendmail.mc:

include(`/usr/share/sendmail-cf/m4/cf.m4')dnl
VERSIONID(`nullclient setup')dnl
OSTYPE(`linux')dnl
FEATURE(`nullclient',`your.mail.server.address.or.name')dnl

It will forward everything to an external mail server except mail addressed to 'root' (at least this is how it works on Centos).

Best Answer

Related Solutions

Centos – Disable local delivery in Sendmail

Sendmail local domain is hosted externally e-mail fails :(

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