Red Hat Knowledgebase

Postfix providers three mechanisms:

always_bcc = address
Deliver a copy of all mail to the specified address.
sender_bcc_maps = type:table
Search the specified "type:table" lookup table with the envelope sender address for an automatic BCC address.
recipient_bcc_maps = type:table
Search the specified "type:table" lookup table with the envelope recipient address for an automatic BCC address.

For example, there are three accounts jerry, john,and berry in the system. The email sent to

jerry, will deliver a copy to john. The email sent from jerry, will deliver a

copy to berry.

Step 1:  create a file named "sender" in /etc/postfix with the following content:

jerry berry

Step 2:  create a file named "receiver" in /etc/postfix with the following content:

jerry john

Step 3: run postmap to create db file.

cd /etc/postfix
postmap hash:sender
postmap hash:receiver

Step 4:  modify /etc/postfix/main.cf , adding the following lines:

recipient_bcc_maps = hash:/etc/postfix/receiver
sender_bcc_maps = hash:/etc/postfix/sender

service postfix restart