IBM Support

How to Configure Sendmail not to Look up MX records.

Technote (troubleshooting)

This document applies only to the following language version(s):



A default sendmail configuration will do DNS queries for MX records, it does this even when its setup to use a Mail Relay Server for sending mail out. This will cause mail to fail if its not able to lookup the MX record.

Resolving the problem

Setting up sendmail not to query DNS for MX records when using a DS (Smart Relay) consists of using "[ ]" brackets around the hostname Mail Relay Server configured in the /etc/mail/

#vi /etc/mail/

Search for DS


change to:


Save the configuration file...

refresh -s sendmail

Cross reference information
Segment Product Component Platform Version Edition
Operating Systems AIX family

Document information

More support for: AIX family

Software version: 5.2, 5.3, 6.1

Operating system(s): AIX

Reference #: T1011217

Modified date: 05 December 2008

Translate this page: