How to make email copy of all sent messages (auto BCC) in Postfix

If you want to make copy of all messages sent through email accout then create file /etc/postfix/sender_bcc with contents:
#emails from #BCC to
from@domain.com bcc@domain.com

Then edit /postfix/main.cf file and add at the end of file

sender_bcc_maps = hash:/etc/postfix/sender_bcc
Finally run commands to read new config:
# postmap /etc/postfix/sender_bcc
# postfix reload

That’s it