Life with Linux

Sender Domain Restriction for Postfix Users : (outgoing) Sometimes we flooded with huge spam mails changing the sender address. So it is very important for a administrator to stop the option for local users. Through the following process sender can send mail only from the allowed domain names as from address domain. Step 1: Add the following line in "main.cf" # vim /etc/postfix/main.cf smtpd_sender_restrictions = check_sender_access hash:/etc/postfix/mydomains, reject_unauth_destination :wq!                 Save and Exit   Step 2:  Create a file in postfix directory.  vim /etc/postfix/mydomains  mydomain1.com         OK  mydomain2.com          OK   :wq!                     ...

Sender Access Check in Postfix: (outgoing) To control unwanted mail sending go for the following steps: Step 1. Add a line in main.cf file: # vim /etc/postfix/ main.cf smtpd_sender_restrictions = hash:/etc/postfix/sender_access Step 2. Create sender_access file and give all the valid users account as following: # vim /etc/postfix/sender_access user1@example.com               OK user2@example.com               OK and more..... :wq!                                          Save and exit the file. Step 3. Run the following Command: postmap /etc/postfix/sender_access Step 4. Restarts postfix service. /etc/init.d...