We will put all of sendmail's configuration files in a separate directory under /etc: /etc/mail. Usually, sendmail will expect these files to reside directly under /etc. To avoid problems, /etc/sendmail.cf should be a symbolic link to /etc/mail/sendmail.cf.
The following files will populate /etc/mail:
aliases - contains additional local addressesgenericsdomain - contains some information on your local host's configurationgenericstable - contains the actual rewriting rules.sendmail.cf - sendmail's configuration filesendmail.mc - the source of sendmail.cf.Some of these files will be accompanied by .db files. They contain hashed databases for sendmail's direct use.
We assume that the cf part of sendmail's source tree resides under a directory named /usr/lib/sendmail.cf. This is the case on Debian GNU/Linux systems. Other distributions will put this stuff at different places. Please refer to your distribution's documentation for details.