Failed to start Postfix : /usr/sbin/postconf: warning: /etc/postfix/main.cf: unused parameter: lmtp-filter_destination_concurrency_limit=2 /usr/sbin/postconf: warning: /etc/postfix/main.cf: unused parameter: smtp-filter_destination_concurrency_limit=2 /usr/sbin/postconf: warning: /etc/postfix/master.cf: unused parameter: lmtp_cache_connection=yes /usr/sbin/postconf: warning: /etc/postfix/master.cf: unused parameter: lmtp_cache_connection=yes /usr/sbin/postconf: warning: /etc/postfix/master.cf: unused parameter: lmtp_cache_connection=yes

Postfix version 2.9.1