How to block / Allow a domain for on Zimbra Mail Server

Sometimes we meet to block any domain to avoid unwanted mail receiving. In this situation, we need to follow the below steps. 

Step:1

vim /opt/zimbra/conf/salocal.cf.in

Add domain name:

 blacklist_from *shopatbest.com
 blacklist_from *trknewsletters.com

or

whitelist_from *dianaimports.com

whitelist_from *nafisabd.com

Step:2

vim /opt/zimbra/conf/amavisd.conf.in

search Positive & Add mark [     # soft-blacklisting (positive score) ]

'.shopatbest.com'                         =>  8.0,       [1-10 value]
'.trknewsletters.com'                    =>  8.0,      

Step:3

zmcontrol restart