NRPE issue

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jiggityjog
Posts: 20
Joined: Mon Apr 22, 2013 5:14 pm

Re: NRPE issue

Post by jiggityjog »

Sure thing. However, I did some sleuthing and found this blog. http://crashatau.blogspot.ca/2007/04/nr ... utput.html

So i check my /var/log/auth file and found lots of these:

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May  9 14:31:21 mortalla sudo:   nagios : 3 incorrect password attempts ; TTY=unknown ; PWD=/ ; USER=root ; COMMAND=/usr/lib/nagios/plugins/check_load -w 1,2,3 -c 2,3,4
May  9 14:31:21 mortalla sudo: unable to execute /usr/sbin/sendmail: No such file or directory
May  9 14:32:07 mortalla sudo:    jason : TTY=tty1 ; PWD=/home/jason ; USER=root ; COMMAND=/usr/bin/pico /etc/nagios/nrpe.cf
The permissions for the plugin directory on the remote server are rwxr-xr-x, owned by nagios:www-data.

Anyway, here are the files you requested.

*NOTE: I've fairly recently added the sudo to the check_load, but that command is basically duplicated and redundant for testing purposes. I've fiddled with it below too, in the services file.

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#############################################################################
# Sample NRPE Config File 
# Written by: Ethan Galstad (nagios@nagios.org)
# 
# Last Modified: 11-23-2007
#
# NOTES:
# This is a sample configuration file for the NRPE daemon.  It needs to be
# located on the remote host that is running the NRPE daemon, not the host
# from which the check_nrpe client is being executed.
#############################################################################


# LOG FACILITY
# The syslog facility that should be used for logging purposes.

log_facility=daemon



# PID FILE
# The name of the file in which the NRPE daemon should write it's process ID
# number.  The file is only written if the NRPE daemon is started by the root
# user and is running in standalone mode.

pid_file=/var/run/nagios/nrpe.pid



# PORT NUMBER
# Port number we should wait for connections on.
# NOTE: This must be a non-priviledged port (i.e. > 1024).
# NOTE: This option is ignored if NRPE is running under either inetd or xinetd

server_port=5666



# SERVER ADDRESS
# Address that nrpe should bind to in case there are more than one interface
# and you do not want nrpe to bind on all interfaces.
# NOTE: This option is ignored if NRPE is running under either inetd or xinetd

#server_address=127.0.0.1



# NRPE USER
# This determines the effective user that the NRPE daemon should run as.  
# You can either supply a username or a UID.
# 
# NOTE: This option is ignored if NRPE is running under either inetd or xinetd

nrpe_user=nagios



# NRPE GROUP
# This determines the effective group that the NRPE daemon should run as.  
# You can either supply a group name or a GID.
# 
# NOTE: This option is ignored if NRPE is running under either inetd or xinetd

nrpe_group=nagios



# ALLOWED HOST ADDRESSES
# This is an optional comma-delimited list of IP address or hostnames 
# that are allowed to talk to the NRPE daemon.
#
# Note: The daemon only does rudimentary checking of the client's IP
# address.  I would highly recommend adding entries in your /etc/hosts.allow
# file to allow only the specified host to connect to the port
# you are running this daemon on.
#
# NOTE: This option is ignored if NRPE is running under either inetd or xinetd

allowed_hosts=192.168.1.3 


# COMMAND ARGUMENT PROCESSING
# This option determines whether or not the NRPE daemon will allow clients
# to specify arguments to commands that are executed.  This option only works
# if the daemon was configured with the --enable-command-args configure script
# option.  
#
# *** ENABLING THIS OPTION IS A SECURITY RISK! *** 
# Read the SECURITY file for information on some of the security implications
# of enabling this variable.
#
# Values: 0=do not allow arguments, 1=allow command arguments

dont_blame_nrpe=1



# COMMAND PREFIX
# This option allows you to prefix all commands with a user-defined string.
# A space is automatically added between the specified prefix string and the
# command line from the command definition.
#
# *** THIS EXAMPLE MAY POSE A POTENTIAL SECURITY RISK, SO USE WITH CAUTION! ***
# Usage scenario: 
# Execute restricted commmands using sudo.  For this to work, you need to add
# the nagios user to your /etc/sudoers.  An example entry for alllowing 
# execution of the plugins from might be:
#
# nagios          ALL=(ALL) NOPASSWD: /usr/lib/nagios/plugins/
#
# This lets the nagios user run all commands in that directory (and only them)
# without asking for a password.  If you do this, make sure you don't give
# random users write access to that directory or its contents!

# command_prefix=/usr/bin/sudo 



# DEBUGGING OPTION
# This option determines whether or not debugging messages are logged to the
# syslog facility.
# Values: 0=debugging off, 1=debugging on

debug=1



# COMMAND TIMEOUT
# This specifies the maximum number of seconds that the NRPE daemon will
# allow plugins to finish executing before killing them off.

command_timeout=60



# CONNECTION TIMEOUT
# This specifies the maximum number of seconds that the NRPE daemon will
# wait for a connection to be established before exiting. This is sometimes
# seen where a network problem stops the SSL being established even though
# all network sessions are connected. This causes the nrpe daemons to
# accumulate, eating system resources. Do not set this too low.

connection_timeout=300



# WEEK RANDOM SEED OPTION
# This directive allows you to use SSL even if your system does not have
# a /dev/random or /dev/urandom (on purpose or because the necessary patches
# were not applied). The random number generator will be seeded from a file
# which is either a file pointed to by the environment valiable $RANDFILE
# or $HOME/.rnd. If neither exists, the pseudo random number generator will
# be initialized and a warning will be issued.
# Values: 0=only seed from /dev/[u]random, 1=also seed from weak randomness

#allow_weak_random_seed=1



# INCLUDE CONFIG FILE
# This directive allows you to include definitions from an external config file.

#include=<somefile.cfg>



# INCLUDE CONFIG DIRECTORY
# This directive allows you to include definitions from config files (with a
# .cfg extension) in one or more directories (with recursion).

#include_dir=<somedirectory>
#include_dir=<someotherdirectory>



# COMMAND DEFINITIONS
# Command definitions that this daemon will run.  Definitions
# are in the following format:
#
# command[<command_name>]=<command_line>
#
# When the daemon receives a request to return the results of <command_name>
# it will execute the command specified by the <command_line> argument.
#
# Unlike Nagios, the command line cannot contain macros - it must be
# typed exactly as it should be executed.
#
# Note: Any plugins that are used in the command lines must reside
# on the machine that this daemon is running on!  The examples below
# assume that you have plugins installed in a /usr/local/nagios/libexec
# directory.  Also note that you will have to modify the definitions below
# to match the argument format the plugins expect.  Remember, these are
# examples only!


# The following examples use hardcoded command arguments...

command[check_users]=/usr/lib/nagios/plugins/check_users 
#command[check_load]=/usr/lib/nagios/plugins/check_load -w 15,10,5 -c 30,25,20
#command[check_hda1]=/usr/lib/nagios/plugins/check_disk -w 20% -c 10% -p /dev/hda1
#command[check_zombie_procs]=/usr/lib/nagios/plugins/check_procs -w 5 -c 10 -s Z
#command[check_total_procs]=/usr/lib/nagios/plugins/check_procs -w 150 -c 200 

command[check_load]=/usr/bin/sudo /usr/lib/nagios/plugins/check_load $ARG1$
command[check_load_nrpe]=/usr/lib/nagios/plugins/check_load $ARG1$
command[check_apt]=/usr/lib/nagios/plugins/check_apt
command[check_users]=/usr/lib/nagios/plugins/check_users $ARG1$


# The following examples allow user-supplied arguments and can
# only be used if the NRPE daemon was compiled with support for 
# command arguments *AND* the dont_blame_nrpe directive in this
# config file is set to '1'.  This poses a potential security risk, so
# make sure you read the SECURITY file before doing this.

#command[check_users]=/usr/lib/nagios/plugins/check_users -w $ARG1$ -c $ARG2$
#command[check_load]=/usr/lib/nagios/plugins/check_load -w $ARG1$ -c $ARG2$
command[check_disk]=/usr/lib/nagios/plugins/check_disk $ARG1$
#command[check_procs]=/usr/lib/nagios/plugins/check_procs -w $ARG1$ -c $ARG2$ -s $ARG3$

#
# local configuration:
#	if you'd prefer, you can instead place directives here
include=/etc/nagios/nrpe_local.cfg

# 
# you can place your config snipplets into nrpe.d/
# only snipplets ending in .cfg will get included
include_dir=/etc/nagios/nrpe.d/

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###############################################################################
# COMMANDS.CFG - SAMPLE COMMAND DEFINITIONS FOR NAGIOS 
###############################################################################


################################################################################
# NOTIFICATION COMMANDS
################################################################################


# 'notify-host-by-email' command definition
define command{
	command_name	notify-host-by-email
	command_line	/usr/bin/printf "%b" "***** Nagios *****\n\nNotification Type: $NOTIFICATIONTYPE$\nHost: $HOSTNAME$\nState: $HOSTSTATE$\nAddress: $HOSTADDRESS$\nInfo: $HOSTOUTPUT$\n\nDate/Time: $LONGDATETIME$\n" | /usr/bin/mail -s "** $NOTIFICATIONTYPE$ Host Alert: $HOSTNAME$ is $HOSTSTATE$ **" $CONTACTEMAIL$
	}

# 'notify-service-by-email' command definition
define command{
	command_name	notify-service-by-email
	command_line	/usr/bin/printf "%b" "***** Nagios *****\n\nNotification Type: $NOTIFICATIONTYPE$\n\nService: $SERVICEDESC$\nHost: $HOSTALIAS$\nAddress: $HOSTADDRESS$\nState: $SERVICESTATE$\n\nDate/Time: $LONGDATETIME$\n\nAdditional Info:\n\n$SERVICEOUTPUT$\n" | /usr/bin/mail -s "** $NOTIFICATIONTYPE$ Service Alert: $HOSTALIAS$/$SERVICEDESC$ is $SERVICESTATE$ **" $CONTACTEMAIL$
	}





################################################################################
# HOST CHECK COMMANDS
################################################################################

# On Debian, check-host-alive is being defined from within the
# nagios-plugins-basic package

################################################################################
# PERFORMANCE DATA COMMANDS
################################################################################


# 'process-host-perfdata' command definition
define command{
	command_name	process-host-perfdata
	command_line	/usr/bin/printf "%b" "$LASTHOSTCHECK$\t$HOSTNAME$\t$HOSTSTATE$\t$HOSTATTEMPT$\t$HOSTSTATETYPE$\t$HOSTEXECUTIONTIME$\t$HOSTOUTPUT$\t$HOSTPERFDATA$\n" >> /var/lib/nagios3/host-perfdata.out
	}


# 'process-service-perfdata' command definition
define command{
	command_name	process-service-perfdata
	command_line	/usr/bin/printf "%b" "$LASTSERVICECHECK$\t$HOSTNAME$\t$SERVICEDESC$\t$SERVICESTATE$\t$SERVICEATTEMPT$\t$SERVICESTATETYPE$\t$SERVICEEXECUTIONTIME$\t$SERVICELATENCY$\t$SERVICEOUTPUT$\t$SERVICEPERFDATA$\n" >> /var/lib/nagios3/service-perfdata.out
	}

define command{
	command_line	$USER1$/check_nrpe -H $HOSTADDRESS$ -t 30 -c $ARG1$ $ARG2$
}
the hosts file

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define host{
	name	linux-box
	use	generic-host
	check_period	24x7
	check_interval	5
	retry_interval	1
	max_check_attempts	10
	check_command	check-host-alive
	notification_period	24x7
	notification_interval	30
	notification_options	d,r
	contact_groups	admins
	register	0
}

define host{
	use	linux-box
	host_name	mortalla
	alias	mortalla.co.ecacs16.ab.ca
	address	192.168.1.33
}

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define service{
	use	generic-service
	host_name	mortalla
	service_description	CPU Load
	check_command	check_nrpe!-c check_load!-a '-w 15,10,5 -c 30,20,10'
}

define service{
	use	generic-service
	host_name	mortalla
	service_description	CPU Load NRPE
	check_command	check_nrpe!check_load_nrpe!-a '-w 15,10,5 -c 30,20,10'
}

define service{
	use	generic-service
	host_name	mortalla
	service_description	apt
	check_command	check_nrpe!check_apt!-a
}

define service{
	use	generic-service
	host_name	mortalla
	service_description	Check Users
	check_command	check_nrpe!check_users
}

define service{
	use	generic-service
	host_name	mortalla
	service_description	Check disk
	check_command	check_nrpe!check_disk!-a '-w 20% -c 10% -p /'
}
abrist
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Posts: 8334
Joined: Thu Nov 15, 2012 1:20 pm

Re: NRPE issue

Post by abrist »

Lets drill down the check_load problem:
The command check_load does not require root access, so you can safely remove the "/usr/bin/sudo" before the command in the nrpe.conf:

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command[check_load]=/usr/lib/nagios/plugins/check_load $ARG1$
From the remote host, try running:

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 su root
su nagios
/usr/lib/nagios/plugins/check_load -w 15,10,5 -c 30,20,10 
If that works, then we need to test it from the nagios server side. On the nagios server, try:

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/usr/local/nagios/libexec/check_nrpe -H <remote host ip> -c check_load -w 15,10,5 -c 30,20,10
Let me know if either of these work/fail/etc.
Former Nagios employee
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lmiltchev
Former Nagios Staff
Posts: 13587
Joined: Mon May 23, 2011 12:15 pm

Re: NRPE issue

Post by lmiltchev »

Change this command definition in the nrpe.cfg file from:

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command[check_load]=/usr/bin/sudo /usr/lib/nagios/plugins/check_load $ARG1$
to:

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command[check_load]=/usr/lib/nagios/plugins/check_load $ARG1$
Restart the daemon, and try your check again. Is it still failing?
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jiggityjog
Posts: 20
Joined: Mon Apr 22, 2013 5:14 pm

Re: NRPE issue

Post by jiggityjog »

Hey guys. So I took the sudo out of the nrpe file and reloaded the service. This picture may be a little confusing. Morta11a (the top one) is my monitoring host. Mortalla, the remote. (Still no output from plugin on the web interface side)

EDIT: I noticed I didn't type exactly the command you specified for the monitoring server abrist (admittedly I lazily used a previous command that looked similar). Though when I tried it your way, I got
./check_nrpe: invalid option -- 'w'
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lmiltchev
Former Nagios Staff
Posts: 13587
Joined: Mon May 23, 2011 12:15 pm

Re: NRPE issue

Post by lmiltchev »

It seems it's working now.
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jiggityjog
Posts: 20
Joined: Mon Apr 22, 2013 5:14 pm

Re: NRPE issue

Post by jiggityjog »

Yeah it does work (it actually took awhile for that to sink in!), but I'm still not getting anything on the web GUI. The only time I ever did was when I used check_nrpe_1arg.
abrist
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Posts: 8334
Joined: Thu Nov 15, 2012 1:20 pm

Re: NRPE issue

Post by abrist »

Have you made sure to restart the nagios process on the nagios server and the nrpe/xinetd service on the remote server?
Former Nagios employee
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VI VI VI - The editor of the Beast!
Come to the Dark Side.
sreinhardt
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Joined: Mon Nov 19, 2012 12:10 pm

Re: NRPE issue

Post by sreinhardt »

You need to remove the -c from your service definition from argument 1. This is already defined in the check command, simply passing check_load for arg1. Everything looks good, I think, provided it has not changed since your posting.
Nagios-Plugins maintainer exclusively, unless you have other C language bugs with open-source nagios projects, then I am happy to help! Please pm or use other communication to alert me to issues as I no longer track the forum.
abrist
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Re: NRPE issue

Post by abrist »

doh. Time for the weekend.
Former Nagios employee
"It is turtles. All. The. Way. Down. . . .and maybe an elephant or two."
VI VI VI - The editor of the Beast!
Come to the Dark Side.
jiggityjog
Posts: 20
Joined: Mon Apr 22, 2013 5:14 pm

Re: NRPE issue

Post by jiggityjog »

Yah definitely reloaded the configuration and rebooted everything; that -c actually kept slipping my mind but I took it out. It shouldn't have mattered since check_load_nrpe was basically a duplicate command. But I'm pretty stumped. I've systematically gone through and amended all (maybe) the permissions, which I think is what opened up NRPE just recently to the monitoring host (or maybe it was editing that sudoers file). I can't see how a firewall would stand between the web interface and the data... Thanks again for the help!
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