For each rule, you must complete a screen composed of these fields.
You can deactivate one rule without erasing it. You must regenerate
the sendmail.cf file and restart Sendmail (linuxconf will
tell you to do so anyway).
The to field contains the original email destination including the full domain name.
It is possible to redirect a full domain by only entering the domain name with the @ character as a prefix (@domain.com). While redirecting a domain is normally done with the special domain routing facility of linuxconf, using complex user routing allows you to redirect a complete domain to a single user account into another domain (this can be very handy!).
You must enter the new email destination. If you wish to redirect the email to another local user, you can simply enter the user account without a domain.
This looks like a simple alias (see "Setting user aliases"). It is
not a replacement for aliases; it is more general. For a large user
base, the normal user alias is more efficient because it uses a
database. The complex user routing should be used to handle exceptions
which can't be solved by normal user aliases. For example, normal user
aliases can't solve this:
Normally, Sendmail will find the proper server based on the Rewritten to field. Sometimes, you may want to impose a server. You just write the fully qualified name here.
If you specify a server, you must specify the protocol to use. Normally esmtp should be used. You can also select uucp-dom when forwarding email through a uucp gateway. This is one case where you will always specify a destination server.
This is just a number used as a hint to sort the rules when generating
the sendmail.cf file. Higher priority means a rule will be entered
first in sendmail.cf. This is normally used when two rules
intersect (one matches a subset of the other). Sendmail matches
rules sequentially. The first match ends the search.
You can write whatever you want here.