How to restrict users to send mail locally in zimbra
This is document can fellow all version of ZCS8.X.X
1:Open smtpd_recipient_restrictions.cf file and add below line
vim /opt/zimbra/conf/zmconfigd/smtpd_recipient_restrictions.cf
check_sender_access lmdb:/opt/zimbra/postfix/conf/restricted_senders
2) Open zmconfigd.cf file and Search “SECTION mta” past just below
vim /opt/zimbra/conf/zmconfigd.cf
POSTCONF smtpd_restriction_classes local_only POSTCONF local_only FILE postfix_check_recipient_access.cf
3) Create below file add below context,
vim /opt/zimbra/conf/postfix_check_recipient_access.cf
check_recipient_access lmdb:/opt/zimbra/postfix/conf/local_domains, reject
4) Create a file restricted_senders” and list all the users, whom you want to restrict.
vim /opt/zimbra/postfix/conf/restricted_senders
user@yourdomain.com1 local_only
user@yourdomain.com2 local_only
5) Create a file “local_domains” and list all the domains where “restricted users” allowed to sent mails
vim /opt/zimbra/postfix/conf/local_domains
mydomain.com OK
6) Run below commands to update and load new Postfix database,
postmap /opt/zimbra/postfix/conf/restricted_senders postmap /opt/zimbra/postfix/conf/local_domains zmmtactl stop zmmtactl start
Important Note if you need to undo above configuration,incase of failure
Remove the two lines that were added to the /opt/zimbra/conf/zmconfigd.cf file. Make sure the Postfix setting smtpd_restriction_classes has nothing set.
postconf -e smtpd_restriction_classes=' '
zmmtactl reload
For more information: Use:https://wiki.zimbra.com/wiki/New_Features_ZCS_8.5#Domain_level_disclaimer_support