Hot answers tagged connection
You can use telnet <host> <port> for example telnet mail.riseup.net 465 For SSL encrypted connections (this likely is one) you can use openssl s_client -connect <host>:<port> for example openssl s_client -connect mail.riseup.net:465 instead if you want to not only test if you can connect but actually talk to the server.
I'd install the swaks package: swaks (Swiss Army Knife SMTP) is a command-line tool written in Perl for testing SMTP setups; it supports STARTTLS and SMTP AUTH (PLAIN, LOGIN, CRAM-MD5, SPA, and DIGEST-MD5). swaks allows one to stop the SMTP dialog at any stage, e.g to check RCPT TO: without actually sending a mail. . If you are spending too ...
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