I’ve often used telnet to connect to random ports to make sure a service is working (eg: telnet somehost.example.com smtp to see if it’s accepting connections on port 25) but have been stuck with a suitable alternative to test connections that are secured with ssl.
Of course openssl is capable of doing this. Simply type:
openssl s_client -connect somehost.example.com:465
This will test an ssl secured connection to the secure smtp (smtps) port on a mail server. Change port number as required.