Nagios Support Forum

Not able monitor linux server using XI, returns below error.


CHECK_NRPE: Error - Could not complete SSL handshake.


# default: on
# description: NRPE (Nagios Remote Plugin Executor)
service nrpe
{
flags = REUSE
socket_type = stream
port = 5666
wait = no
user = nagios
group = nagios
server = /usr/local/nagios/bin/nrpe
server_args = -c /usr/local/nagios/etc/nrpe.cfg --inetd
log_on_failure += USERID
disable = no
only_from = nagiosserverip

Did you forget to restart the daemon after making the changes in /etc/xinetd.d/nrpe?
Do you get the same error if you run the check locally? Add the localhost to the "only_from" line in "/etc/xinetd.d/nrpe" on the remote server :
then run the following command on the remote machine, and show the output:

./check_nrpe -H localhost
NRPE v2.12

Can you show us the command you were trying to monitor the other server with?

./check_nrpe -H IPADRESS

You should be able to get a response back from just running check_nrpe itself to the server as you are, the IP needs to be correct in the allowed_ line, and port 5666 must be open, those should be the only two things causing this error. Can you show us the following file from the remote machine, noting out any public IP's:
Also, do you have telnet installed on your Nagios server? If so, please show the output from the following:

# default: on
# description: NRPE (Nagios Remote Plugin Executor)
service nrpe
{
flags = REUSE
socket_type = stream
port = 5666
wait = no
user = nagios
group = nagios
server = /usr/local/nagios/bin/nrpe
server_args = -c /usr/local/nagios/etc/nrpe.cfg --inetd
log_on_failure += USERID
disable = no
only_from =127.0.0.1,10.nagiosserver

telnet IP 5666
Trying IP...
telnet: connect to address IP: Connection refused
telnet: Unable to connect to remote host: Connection refused

You will need to open port 5666 on tcp/udp in order for NRPE to properly communicate with the server.