Postfix mailer configuration

Postfix mailer configuration
__   _
  -o)/ /  (_)__  __ ____  __      Derek Winterstien
  /\\ /__/ / _ \/ // /\ \/ /      r.o.a.c.h.@.r.o.b.o.t.z...c.o.m
 _\_v __/_/_//_/\_,_/ /_/\_\      Trustix Secure Linux
..............................................................................


Postfix should be configured to start up on boot

   chkconfig Postfix on

Make some configuration changes in postfix

   vi /etc/postfix/main.cf

Add / Modify the following

inet_interfaces = all
mydestination = $myhostname, localhost.$mydomain, $mydomain
myorigin = $mydomain

Logs: (var/log/mail)
  debug
  errors
  info - mail delivery attempts
  notice
  warnings - such as hostname verification

Hosting Domains
----------

1. canonical                   hostname and/or domain of machine
2. virtual alias domain                virtual domain uses unix passwd system
accounts
3. virtual mailbox domain      virtual domain and independent accounts

Configuration: mailbox format
----------

Choose a mailbox format.  This guide will cover mbox as opposed to MailDir.

#!!  home_mailbox = Mailbox <- delete or remark out this line.  Do not specify
     the home_mailbox parameter for mbox style delivery.

  mail_spool_directory = /var/spool/mail

Configuration: main.cf
----------

Edit main.cf

  myorigin

  mydestination

  mynetworks_style     ignord if mynetworks list specified

  mynetworks           you can specify a plain text file to contain valid
relays (ex a10)

  virtual_alias_domains        you can specify a plain text file containing hosted
virtual domains

  virtual_alias_maps   equiv to virtusertable in sendmail, cannot be plain
text file (ex a20)

Example a10:  mynetworks
----------
You can list the relays in the main.cf file:
  mynetworks = 168.100.189.0/28, 127.0.0.0/8
Or refer to a hash file:
  mynetworks = hash:/etc/postfix/relay_table
Or a flat text file:
  mynetworks = /etc/postfix/relay_table
In the flat text file, # comments a line, an IP specifies a single host
allowed relay.  The sendmail format of a partial IP, X.X.X does NOT work.  To
specify a network use network metrics X.X.X.X/24

Example a20: virtual_alias_maps
----------
You can specify a hash table file for virtual_alias_maps, which is simular to
sendmail's 'virtusertable' file with one important difference: postfix virtual
domains do not automatically map to unix system accounts.
  Specify in main.cf:
virtual_alias_maps = hash:/etc/postfix/virtusers
  Format:
username@virtualdomain.com     unixmailbox
  Hash it:
postmap virtusers
  Explained:
The addess username@virtualdomain.com will be directed to the unix system
mailbox named unixmailbox. 

Postfix Lookup Table Types:  type:name
----------
Not all of them, but on Linux here are a few important ones...

regexp regular expressions lookup table
hash   standard hash index file
sdbm   sdbm supported hash index file
pcre   perl style regular expressions table

Virtual Mailbox Domains and Non-UNIX Accounts
----------
You must use a pop or imap server that is compatible with every recipient
address having its own virtual mailbox. For example, popa3d is a great pop
server known for simplicity and security, but it will not recognize your
virtual, non system mailboxes. 

Graylisting and spamd
-----------

http://www.elwood.net/greyspamd.html
http://www.greylisting.org/implementations/postfix.shtml