Sendmail Questions, Problems, and Troubleshooting

1. What are MX records?

   MX records are resource records in the BIND database. Each record contains the name of a target station, a preference level, and the name of an exchanger station that handles mail for the target station. (The exchanger station may be the target station itself.)

   The BIND database can contain several MX records for each target station; the record with the lowest preference level is tried first.

   MX records provide a way to direct mail to alternative stations. Using MX records lets you eliminate static routes from your sendmail configuration file. For more details about setting up MX records, see Appendix B, "IRIX sendmail Reference."

2. sendmail doesn't seem to see my changes to sendmail.cf.

   Remember to save your changes to the configuration file by issuing the following commands:

   /etc/init.d/mail stop

   /etc/init.d/mail start

   The stopping and starting of the daemon forces sendmail to reconfigure the file. Otherwise, sendmail runs using the old, "frozen" version of the configuration file, thus ignoring your changes. For more information on "frozen" configuration files, see Appendix B, "IRIX sendmail Reference."

3. Can I put comments in macro definitions?

   Do not include comments on macro or class definition lines in the sendmail.cf file. For example,

   DDfoo.com # my domain name

   would define the D macro as:

   "foo.com # my domain name"

   Likewise,

   CD foo.com bar.com # my local domains

   would define the D class as containing "foo.com," "bar.com," "#," "my," "local," and "domains."

4. Where can I find information to help me troubleshoot my sendmail installation?

   See Appendix B, "IRIX sendmail Reference."