Nagios Support Forum

Hello

I have a nagios xi license and want to monitor a linux server with debian squeeze.

After installing NRPE version 2.15 and try the command:

/usr/local/nagios/libexec/check_nrpe -n -H localhost

I get the following error: check_nrpe: Response packet had invalid CRC32

in various forums I've found as a solution In inetd mode, force STDERR to map to /dev/null.

But I still have the problem or do not know if I'm doing well.

I hope your help.

Thank you.

Are you seeing this on the nagios server, or via NRPE installed on the debian server? NRPE is used to remotely execute plugins, these plugins can be ran locally without the use of NRPE as well so it does not make a lot of sense to check against localhost with it. Also, did you get an account registered with sales so you can use the XI customer support forums? You are currently posting in the Core General Support forums, which do not pertain to XI. I'm moving this to XI general for now.

Hi!

I was executed the command "/usr/local/nagios/libexec/check_nrpe -n -H localhost" on the Debian server, if I run it from the server NagiosXI get the same error.

Other plugins run fine on Debian server.

Did you compile nrpe with no ssl? Run the following commands on the debian box, and show us the output in code wraps:

nrpe installation was performed using the source file

sending results:

1°:
>ps -ef | grep nrpe
root 11987 11971 0 13:46 pts/0 00:00:00 grep nrpe

2°:
>/usr/local/nagios/bin/nrpe

NRPE - Nagios Remote Plugin Executor
Copyright (c) 1999-2008 Ethan Galstad ([email protected])
Version: 2.15
Last Modified: 09-06-2013
License: GPL v2 with exemptions (-l for more info)
SSL/TLS Available: Anonymous DH Mode, OpenSSL 0.9.6 or higher required

***************************************************************
** POSSIBLE SECURITY RISK - COMMAND ARGUMENTS ARE SUPPORTED! **
** Read the NRPE SECURITY file for more information **
***************************************************************

***************************************************************
** POSSIBLE SECURITY RISK - TCP WRAPPERS ARE NOT AVAILABLE! **
** Read the NRPE SECURITY file for more information **
***************************************************************

Usage: nrpe [-n] -c <config_file> [-4|-6] <mode>

Options:
-n = Do not use SSL
<config_file> = Name of config file to use
-4 = use ipv4 only
-6 = use ipv6 only
<mode> = One of the following operating modes:
-i = Run as a service under inetd or xinetd
-d = Run as a standalone daemon
-d -s = Run as a subsystem under AIX

Notes:
This program is designed to process requests from the check_nrpe
plugin on the host(s) running Nagios. It can run as a service
under inetd or xinetd (read the docs for info on this), or as a
standalone daemon. Once a request is received from an authorized
host, NRPE will execute the command/plugin (as defined in the
config file) and return the plugin output and return code to the
check_nrpe plugin.

3°:
>cat /usr/local/nagios/etc/nrpe.cfg
goes in attachment


Thank you!!

Can you also post the output of the following command?

netstat -at | grep nrpe
tcp 0 0 *:nrpe *:* LISTEN

It doesn't seem nrpe is running as a "standalone" daemon. Otherwise, you would see something like this:
Is it running under xinetd (inetd)? What is the output of the following command?

this is:

cat /etc/xinetd.d/nrpe
# 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 = 127.0.0.1 192.x.x.x
}

Try restarting xinetd:
Then run:
and show us the output.