Ubuntu/Commands/Mail Server CLI/openssl
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Commands | dig | Mail Server CLI | openssl
Example
Connect to mail server - pop or imap
~$ openssl s_client -crlf -connect hostname:port ~$ openssl s_client -crlf -connect pop.gmail.com:25
Connect to smtp mail server
~$ openssl s_client -crlf -starttls smtp -connect hostname:post ~$ openssl s_client -crlf -starttls smtp -conect smtp.gmail.com:25
encode user/pass to base64
~$ echo -n "username" | openssl enc -base64
decode user/pass to base64
~$ echo "username" | openssl enc -base64 -d