Nagios Support Forum

i've been trying to monitor our ticketing system using nagios, however i keep on having trouble connecting to its NRPE port 5666.When i try telnet, Connection was automatically closed by foreign host. Do you have any ideas what's causing this?.

[root ~]# telnet xxx.xx.xxx.xx 5666
Trying xxx.xx.xxx.xx...
Connected to xxx.xx.xxx.xx.
Escape character is '^]'.
Connection closed by foreign host.

As per checking, nrpe is already installed on the machine i'm trying to monitor.I'm also getting an error checking its NRPE

[root libexec]# ./check_nrpe -H xxx.xx.xxx.xx
CHECK_NRPE: Error - Could not complete SSL handshake.

Lee!

Hello @meobeou,

Can you run nmap from Nagios to the NRPE client, it should show port 5666 open or the firewall may Sample Output:

PORT STATE SERVICE
22/tcp open ssh
80/tcp open http
443/tcp closed https
5666/tcp open nrpe

Also, check your NRPE configuration file by following the guide below:

CHECK_NRPE: Error - Could Not Complete SSL Handshake
https://support.nagios.com/kb/category.php?id=93