On 7/8/21 1:59 PM, techli...@phpcoderusa.com wrote:
Any thought how I can troubleshoot this?
map out your traffic one step at a time. connect with openssl s_client curl from an external server, and manually exec an smtp transaction. &/or, less convenietly, (re)send mail from an external mail account, gmail or somesuch. exec tcpdump on each of your listening interfaces/ports, and turn on verbose logging on all your server listeners (named, postfix & dovecot), and identify where the traffic flows to, and where it stops.