Ho avuto l’esigenza di testare la funzionalità di un mailrelay, ma senza che la macchina client disponesse del pacchetto mail:

per ovviare al problema i comadi da lanciare sono pochi e semplici:

$ telnet mailrelay smtp
Connected to mailrelay.
Escape character is ‘^]’.
220 mailrelay ESMTP Exim 4.90_1
HELO mailrelay
250 mailrelay Hello mailrelay [mailrelay]
mail from: user@domain.com
250 OK
rcpt to: user2@otherdomain.com
250 Accepted
data
354 Enter message, ending with “.” on a line by itself
This is test email only

Thanks
.
250 OK id=1j6umb-0005ko-VZ
quit
221 mailrelay closing connection
Connection closed by foreign host.
$

Fatto !