sendmail, 4th Edition

Install sendmail

There are two approaches to installing a new sendmail:

• If you choose to run the new sendmail in place of the original, you first need to create and install a new configuration file. The m4(1) program is used to automate the process of configuration file creation. See Chapter 17 on page 584 for a full description of this process.

• If you choose to keep the original and install the new sendmail in parallel (until you can test it), you can proceed with the installation and defer configuration files until later. Note that this choice presumes you customized the file locations.

After you have compiled sendmail (and if the configuration file is ready and tested), you can install it as your production version. If you are already running a sendmail and will be overwriting that binary, you will need to kill that version first (Daemon mode (-bd) on page 20).

Beginning with V8.12,^[35] installation of sendmail became a bit more complex. You now have the choice of running sendmail as either a set-user-id root or a non-set-user-id root program. Our recommendation, beginning with V8.12, is to run sendmail as a non-set-user-id root. If you wish to install sendmail as a set-user-id root program, despite the potential security risks implied by such an approach, just issue this new special command:

# ./Build install-set-user-id

The preferred way to install sendmail, beginning with V8.12, is to first create three required system changes, and then to run ./Build install as usual:

• Edit the ...