Examine the sendmail.cf file on your system. Although you don't yet know what any of it does, you should be delightfully surprised to discover that you already know what most of the configuration commands are generally meant to do.
Determine how your site is organized. Is it arranged to be convenient for users or for the administrator? Are the two necessarily exclusive?
If you are running a vendor-supplied V8 sendmail, the
V configuration command may modify how sendmail
behaves. That is, there may be vendor-specific text following
the version number (such as
/sun). If so, read your
online documentation to find what has been modified.