poorman's enterprise mail server

mailsrv

(mainly quoted from http://n3mesisfixx.blogspot.com/2013/07/configuring-exim4-to-route-to-many.html)

0. manage domain "enterprisedomain.com" and mx record and PTR/ip reverse name
1. install debian
2. setup exim4 domains
   run $dpkg-reconfigure exim4-config'
   set "type" as internet
   set "mail name" to *somelocalname* eg. debian or change /etc/mailname+/etc/hosts
   set "other dest domain"/dc_other_hostnames as "*somelocalname*; enterprisedomain.com;", make sure *somelocalname* in the list.
3. enable virtual alias
  edit /etc/exim4/exim4.conf.template, add:

  #####################################################
  # router/350_exim4-config_virtual_aliases
  #####################################################
   
  #---------------------------
  # This router is added so that we can use this server for multiple domains
  # And also be able to define custom aliases for each of these domains...
  # NOTE : this router is placed before the system_aliases router so that virtual domain
  #        routing takes precedence over system_aliases
  #----------------------------
   
  #allows for aliases of the sort==> [email protected] : local_user, [email protected]
   
  domains_virtual:
          driver = redirect
          data = ${lookup{$local_part@$domain}lsearch{/etc/exim4/aliases.virtual}}
   
  #allows for a special catch-all alias of the sort==> @host.com : local_user, [email protected]
  
  domains_virtual_others:
          driver = redirect
          data = ${lookup{@$domain}lsearch{/etc/exim4/aliases.virtual}}
  
  #####################################################
  # end router/350_exim4-config_virtual_aliases
  #####################################################

between 300 and 400, as https://gist.github.com/mcnemesis/5928364#file-350_exim4-config_virtual_aliases and 

4. setup alias
  edit /etc/exim4/aliases.virtual as lines of "*@enterprisedomain.com: somelocaluser"
5. set correct from field from to field when reply
  edit ~somelocaluser/.muttrc, add:
  
   alternates ^[email protected]$ ^[email protected]$ ^[email protected]$
   set reverse_name=yes
   
  (http://dev.mutt.org/trac/wiki/UseCases/MultiAccounts)
  
6. override return path to postmaster
  edit /etc/exim4/exim4.conf.template, check MAIN_FORCE_SENDER not enabled or add somelocaluser as trusted user:

   trusted_users = MAIN_TRUSTED_USERS : somelocaluser

  edit ~somelocaluser/.muttrc, add:

   set use_envelope_from
   set envelope_from_address="[email protected]"

7. stripe local delivery transport header
  edit /etc/exim4/exim4.conf.template, in remote_smtp section, add:

   headers_remove = Received

  or:

   received_header_text = ""

Mesage-ID should not be removed from header, otherwise will be regarded as spam.
http://www.google.com/mail/help/bulk_mail.html