To send an email over openssl from Linux you only need an open terminal and the openssl package installed. Then it is simply a matter of opening a connection to your server and sending it some commands. It is the same commands that your GUI mail client will be using.
To send an email with telnet from Linux you only need an open terminal and telnet. Then it is simply a matter of opening a connection to your server and sending it some commands. It is the same commands that your GUI mail client will be doing.
To Test a POP3 Mailserver from Linux you only need an open terminal, telnet or openssl installed. Then it is simply a matter of opening a connection to your server and sending it some commands. It is the same commands that your GUI mail client will be doing.
To Test an IMAP Mailserver from Linux you only need an open terminal, telnet or openssl installed. Then it is simply a matter of opening a connection to your server and sending it some commands. It is the same commands that your GUI mail client will be doing.