When configuring a Linux computer running sendmail
you must/can do the following things:
You must minimally specify the intended purpose of your computer, mail-wise: is it a workstation or the mail server? What is the domain used for email? Etc.
You can set up exceptions in routing. If you know a short cut to a specific site or domain, you can tell sendmail here. This is especially needed to connect uucp sites to the Internet.
This allows you to do mail routing based on the user and the destination domain. It is then possible to handle email to a domain one way and also perform some exceptions for few users of this domain. This feature is not a replacement for normal user aliasing, although it performs, at first sight, the same thing.
You can define filters that replace the sender/domain of an email by another sender and or domain. This is handy for some broken mail gateways which send email with a bogus return address. If your Linux server is in the path, you can fix it!
This allows your server to route email messages to your fax engine. It supports various access control rules. Mail to fax offers a universal protocol for faxing from a computer, which is easy to use and usable by any user/operating system.
A virtual email domain lets you set one independent user list, per domain, on the same server. Further, each virtual email domain may have its own administrator(s).
This ability eases the management of user accounts, since each domain has its own list. Further, virtual email domains may be moved from server to server very easily to balance loads.
This is a must for large organizations and ISPs.
Some users may want to receive their email under different
names, or you may want to set a "pseudo" user and direct
the mail of this user to a real one. Good examples
are postmaster, info and support.
Virtual domains have their own user aliases lists.
Sendmail is configured using the file
/etc/sendmail.cf.
This file contains complex configuration commands which resembles
a programming language more than a configuration
file. For this reason, this file is not edited by
linuxconf, but generated from scratch each time.
When using this menu option, linuxconf prompts you to make sure you really want to generate this file.
If you do various modifications in the sendmail configuration using Linuxconf, it will suggest that you generate a new sendmail.cf to make these configuration changes active.
See the comments at the beginning of /etc/sendmail.cf
to see how it is built and how manual modifications can be done
(this is for experts only!).
This dialog lets you enter the email addresses, domains and IP numbers from which you never want to receive email.
You can enter the hosts and networks for which you will accept relay mail. You generally enter your own IP networks and a few other sendmail servers and user workstations here.
Same as above, except that you enter hosts and domains here, not IP numbers.
You enter the names, IP numbers, networks, and domains for which you will accept relaying.