This happened to a Plesk 8.x Linux (RH) server, the problem was that smtp service was up and running, and the queue was very light , but smtp wouldn’t accept any connections at port 25 even from localhost.
In the /var/log/messages I saw this disturbing message:
xinetd[#]: Deactivating service smtp due to excessive incoming connections. Restarting in 30 seconds.
If you see a lot of smtp connections or your server gets constantly in spam black lists, maybe you should check if some bot spams through your server.
The are 2 cases of spamming through a box:
1)using unsecure php forms that bots abuse
2)using smtp connection from an outside client
this artice is about the 2nd case,
I guess most of you did face situtation where you type top and see a lots of unknown or mysterious scripts/utils running that take over top screen and your machine resources.
most of the times these scripts (like the irc bots that I encountered) run via perl and disguise them selfs using names like : /usr/local/apache/bin/httpd -DSSL
ofcourse if you try to kill one another 100 run in the same time, so the best way is to
They way to do such change in plesk 7,5 and in 8,x is different so follow the instructions below:
Run the command telnet [host] port
for example:
-telnet mail.domain.tld 25
Right after the connection is established (more…)
Did you ever needed to use CTRL-ALT-DEL through a Remote Desktop Connection?