How to specifically limit the number of recipients in TO, CC and BCC
In just 2 mins
1) If you wish to limit the total number of recipients in an email, you can do that using the variable ‘smtpd_recipient_limit=10’
# postconf -e ‘smtpd_recipient_limit=10’
# /etc/init.d/postfix restart
2) If you wish to specifically limit the number if recipients in TO and CC. You can do that with the option in main.cf:
header_checks = regexp:/etc/postfix/header_checks
contents of /etc/postfix/header_checks
/^To:([^@]*@){50,}/ REJECT Sorry, your message has too many recepients.
/^Cc:([^@]*@){50,}/ REJECT Sorry, your message has too many recepients.
This will not work for BCC. By the time the message gets to header_checks, the BCC header will be already removed.
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