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Return code of 255 for service 'CPU Load' on hos

Posted: Mon Mar 30, 2020 10:34 am
by dheerushops
I have installed nrpe agent and added remote server in Nagios Monior server.
Server: nagioshost


CPU Load CRITICAL (Return code of 255 for service 'CPU Load' on host 'nagioshost' was out of bounds)

Current Users CRITICAL (Return code of 255 for service 'Current Users' on host 'nagioshost' was out of bounds)

HTTP CRITICAL connect to address 66.248.x.x and port 80: No route to host

SSH Monitoring CRITICAL (Return code of 255 for service 'SSH Monitoring' on host 'nagioshost' was out of bounds)

Total Processes CRITICAL (Return code of 255 for service 'Total Processes' on host 'nagioshost' was out of bounds)

Re: Return code of 255 for service 'CPU Load' on hos

Posted: Mon Mar 30, 2020 1:34 pm
by dheerushops
while I am running the command on linux host to check the services its fine and providing expected results.

but not working from nagios core GUI.

Re: Return code of 255 for service 'CPU Load' on hos

Posted: Mon Mar 30, 2020 7:28 pm
by Box293
Please post your nagios configuration that shows your configurations for this service.

Re: Return code of 255 for service 'CPU Load' on hos

Posted: Tue Mar 31, 2020 7:34 am
by dheerushops
[root@nagioshost ~]# cat /usr/local/nagios/etc/nrpe.cfg
#############################################################################
# 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/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 localhost 66.248.241.249



# 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. Network addresses with a bit mask
# (i.e. 192.168.1.0/24) are also supported. Hostname wildcards are not currently
# supported.
#
# 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=127.0.0.1



# 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=0



# BASH COMMAND SUBTITUTION
# This option determines whether or not the NRPE daemon will allow clients
# to specify arguments that contain bash command substitutions of the form
# $(...). This option only works if the daemon was configured with both
# the --enable-command-args and --enable-bash-command-substitution configure
# script options.
#
# *** ENABLING THIS OPTION IS A HIGH SECURITY RISK! ***
# Read the SECURITY file for information on some of the security implications
# of enabling this variable.
#
# Values: 0=do not allow bash command substitutions,
# 1=allow bash command substitutions

allow_bash_command_substitution=0



# 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=0



# 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/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/local/nagios/libexec/check_users -w 5 -c 10
command[check_load]=/usr/local/nagios/libexec/check_load -w 15,10,5 -c 30,25,20
command[check_hda1]=/usr/local/nagios/libexec/check_disk -w 20% -c 10% -p /dev/hda1
command[check_zombie_procs]=/usr/local/nagios/libexec/check_procs -w 5 -c 10 -s Z
command[check_total_procs]=/usr/local/nagios/libexec/check_procs -w 150 -c 200
command[check_ssh]=/usr/local/nagios/libexec/check_ssh -H 66.248.243.249
command[check_http]=/usr/lib64/nagios/plugins/check_http -H 66.248.243.249 -I 66.248.243.249

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


#allowed_hosts=127.0.0.1

[root@SNC-Tools-VM02 ~]#

Re: Return code of 255 for service 'CPU Load' on hos

Posted: Tue Mar 31, 2020 3:36 pm
by Box293
Your config seems fine.
dheerushops wrote:while I am running the command on linux host to check the services its fine and providing expected results.

but not working from nagios core GUI.
Can you provide an example of running that command on the command line from the linux host and then also provide the command you are using to test from the Nagios host.

Re: Return code of 255 for service 'CPU Load' on hos

Posted: Wed Apr 01, 2020 4:04 am
by dheerushops
[root@nagioshost ~]# /usr/local/nagios/libexec/check_users -w 5 -c 10
USERS OK - 1 users currently logged in |users=1;5;10;0
[root@nagioshost ~]# /usr/local/nagios/libexec/check_nrpe -H localhost -c check_total_procs
PROCS WARNING: 174 processes | procs=174;150;200;0;
[root@nagioshost ~]# /usr/local/nagios/libexec/check_nrpe -H localhost -c check_load
OK - load average: 0.01, 0.02, 0.05|load1=0.010;15.000;30.000;0; load5=0.020;10.000;25.000;0; load15=0.050;5.000;20.000;0;
[root@nagioshost ~]#

Re: Return code of 255 for service 'CPU Load' on hos

Posted: Wed Apr 01, 2020 7:53 am
by scottwilkerson
dheerushops wrote:[root@nagioshost ~]# /usr/local/nagios/libexec/check_users -w 5 -c 10
USERS OK - 1 users currently logged in |users=1;5;10;0
[root@nagioshost ~]# /usr/local/nagios/libexec/check_nrpe -H localhost -c check_total_procs
PROCS WARNING: 174 processes | procs=174;150;200;0;
[root@nagioshost ~]# /usr/local/nagios/libexec/check_nrpe -H localhost -c check_load
OK - load average: 0.01, 0.02, 0.05|load1=0.010;15.000;30.000;0; load5=0.020;10.000;25.000;0; load15=0.050;5.000;20.000;0;
[root@nagioshost ~]#
If would give us a better understanding if you ran this against the remote host from the nagios server
example, from the Nagios server

Code: Select all

/usr/local/nagios/libexec/check_nrpe -H REMOTEHOST -c check_load
echo $?

Re: Return code of 255 for service 'CPU Load' on hos

Posted: Wed Apr 01, 2020 9:39 am
by dheerushops
Thank you scottwilkerson and Box293 for response:

[root@nagiosserver ~]# /usr/local/nagios/libexec/check_nrpe -H X.X.X.X -c check_load
connect to address X.X.X.X port 5666: No route to host
connect to host X.X.X.X port 5666: No route to host
[root@nagiosserver ~]#



When I checked iptables service is running. I have stopped the iptables service.


[root@nagioshost ~]# service iptables status
Redirecting to /bin/systemctl status iptables.service
● iptables.service - IPv4 firewall with iptables
Loaded: loaded (/usr/lib/systemd/system/iptables.service; enabled; vendor preset: disabled)
Active: active (exited) since Thu 2020-03-26 03:07:29 EDT; 6 days ago
Process: 1200 ExecStart=/usr/libexec/iptables/iptables.init start (code=exited, status=0/SUCCESS)
Main PID: 1200 (code=exited, status=0/SUCCESS)
Tasks: 0
Memory: 0B
CGroup: /system.slice/iptables.service

Mar 26 03:07:28 nagioshost systemd[1]: Starting IPv4 firewall with iptables...
Mar 26 03:07:29 nagioshost iptables.init[1200]: iptables: Applying firewall rules: [ OK ]
Mar 26 03:07:29 nagioshost systemd[1]: Started IPv4 firewall with iptables.
[root@nagioshost ~]# service iptables stop
Redirecting to /bin/systemctl stop iptables.service
[root@nagioshost ~]#


After stopping iptables in nagioshost server, we are getting output from nagiosserver:
[root@nagiosserver ~]# /usr/local/nagios/libexec/check_nrpe -H X.X.X.X -c check_load
OK - load average: 0.00, 0.01, 0.05|load1=0.000;15.000;30.000;0; load5=0.010;10.000;25.000;0; load15=0.050;5.000;20.000;0;
[root@nagiosserver ~]#

Re: Return code of 255 for service 'CPU Load' on hos

Posted: Wed Apr 01, 2020 9:46 am
by dheerushops
Can you please provide threshold values for below services :

CPU Utilization
MEM Utilization
SWAP Utilization
FILE System Utilization
Ping / Availability of Servers


Below is the lscput output from nagioshost:
[root@nagioshost~]# lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 176
On-line CPU(s) list: 0-175
Thread(s) per core: 2
Core(s) per socket: 22
Socket(s): 4
NUMA node(s): 4
Vendor ID: GenuineIntel
CPU family: 6
Model: 79
Model name: Intel(R) Xeon(R) CPU E7-8880 v4 @ 2.20GHz
Stepping: 1
CPU MHz: 2600.039
CPU max MHz: 3300.0000
CPU min MHz: 1200.0000
BogoMIPS: 4389.79
Virtualization: VT-x
L1d cache: 32K
L1i cache: 32K
L2 cache: 256K
L3 cache: 56320K
NUMA node0 CPU(s): 0-21,88-109
NUMA node1 CPU(s): 22-43,110-131
NUMA node2 CPU(s): 44-65,132-153
NUMA node3 CPU(s): 66-87,154-175



And I have set as below:
[root@nagioshost~]# cat /usr/local/nagios/etc/nrpe.cfg |grep load
command[check_load]=/usr/local/nagios/libexec/check_load -w 15,10,5 -c 30,25,20
[root@nagioshost~]#
please help what values I can put for Warning and Critical for CPU load service ?

Re: Return code of 255 for service 'CPU Load' on hos

Posted: Wed Apr 01, 2020 4:34 pm
by Box293
OK so the problem should be the firewall rules need to be opened on your remote server or you disable the firewall on it. The following KB article shows you how to define firewall rules:

https://support.nagios.com/kb/article/n ... s-617.html
dheerushops wrote:please help what values I can put for Warning and Critical for CPU load service ?
The standard values are acceptable however every environment is different, this is something you need to determine based on the default load on your servers. The check library is a great resource that explains a lot of the common plugins but you will need to work out your own thresholds:

https://support.nagios.com/kb/category.php?id=186