Solution Connect to FortiGate via SSH session or GUI > Dashboard > Console, select either of commands following
1) smtptest
#mail # execute smtptest 10.47.0.174 Connected
220 smtp.shathish.org ESMTP Smtpd; Wed, 2 Oct 2019 07:07:45 +0800
Entering interactive mode. Type CTRL-D to exit. ehlo 10.47.0.209 250-smtp.shathish.org Hello [10.47.0.209], pleased to meet you 250-ENHANCEDSTATUSCODES 250-PIPELINING 250-8BITMIME 250-SIZE 20971520 250-DSN 250-STARTTLS 250-DELIVERBY 250 HELP mail from: test@pulltea.net 250 2.1.0 test@pulltea.net... Sender ok rcpt to:shathish@shathish.org 250 2.1.5 shathish@shathish.org... Recipient ok data 354 Enter mail, end with "." on a line by itself Subject: test sending email Message body . 250 2.0.0 x91N7jMj021874-x91N7jMk021874 Message accepted for delivery quit 221 2.0.0 smtp.shathish.org closing connection Connection closed.
Connection status to 10.47.0.174 port 25: Connecting to remote host succeeded.
mail #
2) Telnettest
#execute telnettest 10.47.0.174:25 Connected
220 smtp.shathish.org ESMTP Smtpd; Wed, 2 Oct 2019 07:10:45 +0800
Entering interactive mode. Type CTRL-D to exit. ehlo 10.47.0.209 250-smtp.shathish.org Hello [10.47.0.209], pleased to meet you 250-ENHANCEDSTATUSCODES 250-PIPELINING 250-8BITMIME 250-SIZE 20971520 250-DSN 250-STARTTLS 250-DELIVERBY 250 HELP mail from: test@pulltea.net 250 2.1.0 test@pulltea.net... Sender ok rcpt to:shathish@shathish.org 250 2.1.5 shathish@shathish.org... Recipient ok data 354 Enter mail, end with "." on a line by itself Subject: test sending email Message body . 250 2.0.0 x91N7jMj021874-x91N7jMk021874 Message accepted for delivery quit 221 2.0.0 smtp.shathish.org closing connection Connection closed.
Connection status to 10.47.0.174 port 25: Connecting to remote host succeeded.
