Scenario: I am managing a Postfix 2.10 installation acting as an hub for applications sending emails to the internet. The Postfix installation in turn uses a relayhost that is an A record resolving to n IP addresses; TLS to the relayhosts is negotiated opportunistically anyway it always succeeds.
I suspect connection caching is not available as per http://www.postfix.org/CONNECTION_CACHE_README.html "With Postfix versions < 3.4, the Postfix shared connection cache cannot be used with TLS, because an open TLS connection can be reused only in the process that creates it. For this reason, the Postfix smtp(8) client historically always closed the connection after completing an attempt to deliver mail over TLS." Is that true also in case of relayhost? Also I cannot find in the doc how many email transactions are performed during an SMTP over TLS connection. Thanks Luca Fornasari
