How to check that SMTP Plesk service is running OK on the server?
Verify either port 25 is listening by performing the following command:
# netstat -ntap | grep 25 tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN -
Log in to the Plesk server and try command
telnet localhost 25. If SMTP works and Qmail is used as a mail server, the output should be:
# telnet localhost 25 Trying 127.0.0.1... Connected to localhost.localdomain (127.0.0.1). Escape character is '^]'. 220 hostname.tld ESMTP
or in case Postfix is used:
# telnet localhost 25 Trying 127.0.0.1... Connected to localhost.localdomain (127.0.0.1). Escape character is '^]'. 220 hostname.tld ESMTP Postfix
If you run
telnet localhost 25 on the Plesk server and see another greeting, check article 1374.
If you see an error in
smtp/tcp server failing (looping), service terminated
try an article 1470.
For FreeBSD users. On Plesk for FreeBSD, SMTP is run using 'inetd' super-server. You should check that the 'inetd' process is running and that the /etc/inetd.conf contains records for Plesk SMTP service.