Step 2: Enable BCC forwarding For All Users

To archive mail from your primary email domain hosted on Postfix, follow the steps mentioned below. This forwards mail from the primary email server to the Vaultastic servers.

Assume the Postfix configuration files are in /etc/postfix.
cd /etc/postfix
dit main.cf
search for always_bcc and include the following line: 

1. In main.cf

   # Add the following lines
   sender_bcc_maps=pcre:/etc/postfix/sender_bcc_map
   recipient_bcc_maps=pcre:/etc/postfix/recipient_bcc_map

2. In /etc/postfix/sender_bcc_map

   # Add line for each domain archiving to vaultastic
   # replace . (dot) in domain name with \. (slash dot)
   # For example domain acmecorp.com: /^(.*)@acmecorp\.com$/ $1@acmecorp.vaultastic.com
   /^(.*)@{domainname}$/ $1@{domainprefix}.vaultastic.com

3. In /etc/postfix/recipient_bcc_map

   # Add line for each domain archiving to vaultastic
   # replace . (dot) in domain name with \. (slash dot)
   # For example domain acmecorp.com: /^(.*)@acmecorp\.com$/ $1@acmecorp.vaultastic.com
   /^(.*)@{domainname}$/ $1@{domainprefix}.vaultastic.com

4. Configure Transports

   Edit transport add the following line before all the routes

   {domainprefix}.vaultastic.com smtp:send-v4.vaultastic.com:25

   For example domain acmecorp.com:

   acmecorp.vaultastic.com smtp:send-v4.vaultastic.com:25

   Save transport file

   postmap /etc/postfix/transport

5. Reload postfix

   /etc/init.d/postfix reload