The message transport agent
Mail user agents
Message store
The Mail Manager
Default configuration
Managing aliases
Managing domains
Masquerading or domain hiding
Domain tables
sendmail.cf implementation of the domain table
Domain table format
Configuring INBOX locations
Managing mail channels
The default channels
The UUCP channel
The baduser channel
The badhost channel
sendmail.cf implementation of mail channels
Channel tables
Channel delivery
Managing virtual domains
How virtual domains work
Enabling virtual domains
Warnings for users in virtual domains
Managing aliases in virtual domains
Managing spam
Blocking spam email from known offenders
Blocking spam email using the MAPS Realtime Blackhole List
Prevention of forged-spam email via sendmail (relay disable)
Email spam detection method for ISPs