Specific emails ID only receive mail from specific domains:

Step 1. At first edit the main.cf file of postfix.

# vim /etc/postfix/main.cf

smtpd_recipient_restrictions = check_recipient_access hash:/etc/postfix/protected_destinations, permit_mynetworks, reject_unauth_destination

smtpd_restriction_classes = insiders_only

insiders_only = check_sender_access hash:/etc/postfix/insiders, reject

[Explanation: smtpd_recipient_restrictions is a postfix parameter, It will check the recipient access by "protected_destinations"- Lets see below what I will put in "protected_destinations"? ]

Step 2. Edit and save the following in

# vim /etc/postfix/protected_destinations

    xyz@domain.com   insiders_only

    

[How do postfix knows insider_only?? It has been declared in main.cf with "smtpd_restriction_classes" after that I defined the "insiders_only" in postfix by "/etc/postfix/insiders".]

Step 3. Now input /etc/postfix/insiders

# /etc/postfix/insiders

   domain.com                      OK       ###matches my.domain and subdomains

   anotherdomain.com        OK       ###matches another.domain and subdomains

Step 4. Now create .db for new files with following commands.

# postmap /etc/postfix/insiders

# postmap /etc/postfix/protected_destinations

Step 5.Restart the postfix service.

# /etc/init.d/postfix restart

Now mentioned Mail ID  cannot received any mail from mentioned Domain   :)