Nagios Support Forum

Hi

We are testing Nagios Agent on CentOS8 and I have come across 1 issue
I have tried a few thing but nothing seems to have corrected the problem

If I go to Configure, Core Configure manager and then Services
I goto one of the servers that the check_cpu monitor works on

So the command is basically
Check Command = check_nrpe
$ARG1$ = check-cpu

so if I click on the "Test Check Command" Button
and paste in one of our RHEL6 Servers I get the following details
COMMAND: /usr/local/nagios/libexec/check_nrpe -H bwylbopjiras02 -t 30 -c check_cpu
OUTPUT: DM-CPU OK - Idle=98.25% | user=1.05%;60;70 nice=0.00%;60;70 system=0.60%;60;70 idle=98.25%;100;100 iowait=0.10%;80;90 irq=0.00%;60;70 softirq=0.00%;60;70


If I Do the same but specify the hostname of the new CentOS 8 Server I just get the following
COMMAND: /usr/local/nagios/libexec/check_nrpe -H dwylbopsndbx14 -t 30 -c check_cpu
OUTPUT: NRPE: Unable to read output


The two systems have both got the same configuration of the nrpe.cfg files
On the new CentOS 8 system we have 4 monitors configured

/Disk Usage This is configured as - check_nrpe check_disk
Load This is configured as - check_nrpe check_load
Memory Usage This is configured as - check_nrpe check_mem

These 3 work fine so this is why I am puzzled

any help would be appreciated

Thanks

Sorry just a quick question came to mind
Is there any prerequisites that need to be installed for the nagios Agent to work correctly ?

Did you follow the document below when installing the Linux agent on your CentOS 8 machine?

https://assets.nagios.com/downloads/nag ... _Agent.pdf

Is there any prerequisites that need to be installed for the nagios Agent to work correctly ?

I didn't have any issues with installing the agent on CentOS 8. The installer script should take care of prerequisites. Having said that, I would like to mention that the command that is created is "check_cpu_stats", not "check_cpu". It is added to the common.cfg file.

Example:
On the client On the server Can you post the nrpe.cfg and common.cfg files from the client on the forum?

Also, run the following commands on the Nagios XI server from the command line, and show the output:

Hi
Sorry turns out the test system I have been given is a Red Hat 8 and not a CentOS8
The previous systems was CentOS8 but I cannot modify that system

I have done a search for common.cfg but no files where found on the system
So I got a test system and uninstalled the version of Nagios Agent
and then followed the link above to download and do a install

But when I run the ./fullinstall command I get the following message

[root@dwylbopsndbx19 linux-nrpe-agent]# ./fullinstall
RedHatEnterprise is not currently supported. Please use either Red Hat, CentOS, Oracle Linux, CloudLinux, SUSE Enterprise, OpenSUSE, Ubuntu, or Debian.
[root@dwylbopsndbx19 linux-nrpe-agent]#

[root@dwylbopsndbx19 linux-nrpe-agent]# lsb_release -i -r
Distributor ID: RedHatEnterprise
Release: 8.1


The Linux team install the agent via puppet code but when I reinstalled the agent I did get the following message

Notice: /Stage[main]/Opnagios::Profile::Nagios_agent/Package[nrpe]/ensure: created
Error: Execution of '/usr/bin/yum -d 0 -e 0 -y install nagios-plugins-lcgdm-common' returned 1:
Error: /Stage[main]/Opnagios::Profile::Nagios_agent/Package[nagios-plugins-lcgdm-common]/ensure: change from purged to present failed: Execution of '/usr/bin/yum -d 0 -e 0 -y install nagios-plugins-lcgdm-common' returned 1:

Thanks

So I got a test system and uninstalled the version of Nagios Agent
and then followed the link above to download and do a install

But when I run the ./fullinstall command I get the following message

[root@dwylbopsndbx19 linux-nrpe-agent]# ./fullinstall
RedHatEnterprise is not currently supported. Please use either Red Hat, CentOS, Oracle Linux, CloudLinux, SUSE Enterprise, OpenSUSE, Ubuntu, or Debian.

I think this is a bug in our installer, as it checks for the output of "lsb_release -si" first, but then the "RedHatEnterprise" option is not included as a supported distro... I didn't have "lsb_release" on my test RHEL 8 system, so the installer worked for me. Anyway, I will be notifying our developers of the issue. Meanwhile, you can modify the "fullinstall" script by changing line 87 from this: to this: Save, exit. Now the installer should work, provided you installed dev tools. FYI, here's the repos I have on my test box: just to give you an idea of my test environment. Hope this helps.

The Linux team install the agent via puppet code but when I reinstalled the agent I did get the following message

Notice: /Stage[main]/Opnagios::Profile::Nagios_agent/Package[nrpe]/ensure: created
Error: Execution of '/usr/bin/yum -d 0 -e 0 -y install nagios-plugins-lcgdm-common' returned 1:
Error: /Stage[main]/Opnagios::Profile::Nagios_agent/Package[nagios-plugins-lcgdm-common]/ensure: change from purged to present failed: Execution of '/usr/bin/yum -d 0 -e 0 -y install nagios-plugins-lcgdm-common' returned 1:

This is out of scope of Nagios support. You would need to remove all of the custom packages installed by puppet and try our official installer.

Hi

I have just edited the fullinstall script and added the line you mentioned
But now when I run the Fullinstall script I got the following message

Nagios Linux Agent Installation Log
===================================
DATE: Wed Apr 15 03:54:15 EDT 2020

DISTRO INFO:
RedHatEnterprise
8.1
x86_64

Configuring Repos...
Repos configured OK
Installing prerequisites...
Prerequisites installed OK
Adding users and groups...
useradd: user 'nagios' already exists
groupadd: group 'nagios' already exists
useradd: user 'nagios' already exists
Users and groups added OK
/etc/services updated
Firewall rules updated OK
SUB
NAGIOSPLUGINS
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /usr/bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether to disable maintainer-specific portions of Makefiles... yes
checking build system type... x86_64-unknown-linux-gnu
checking host system type... x86_64-unknown-linux-gnu
checking for gcc... no
checking for cc... no
checking for cl.exe... no
configure: error: in `/tmp/linux-nrpe-agent/subcomponents/nagiosplugins/nagios-plugins-2.2.1':
configure: error: no acceptable C compiler found in $PATH
See `config.log' for more details.

real 0m7.385s
user 0m0.136s
sys 0m0.150s
make: *** No rule to make target 'clean'. Stop.

real 0m0.003s
user 0m0.001s
sys 0m0.002s
make: *** No targets specified and no makefile found. Stop.

real 0m0.003s
user 0m0.003s
sys 0m0.000s
make: *** No rule to make target 'install'. Stop.

real 0m0.003s
user 0m0.001s
sys 0m0.001s

real 0m7.840s
user 0m0.225s
sys 0m0.287s
Subcomponents installation failed - exiting


Thanks

The config.log file basically gives the same message

## ----------- ##
## Core tests. ##
## ----------- ##

configure checking for a BSD-compatible install
configure result: /usr/bin/install -c
configure checking whether build environment is sane
configure result: yes
configure checking for a thread-safe mkdir -p
configure result: /usr/bin/mkdir -p
configure checking for gawk
configure found /usr/bin/gawk
configure result: gawk
configure checking whether make sets $(MAKE)
configure result: yes
configure checking whether to disable maintainer-specific portions of Makefiles
configure result: yes
configure checking build system type
configure result: x86_64-unknown-linux-gnu
configure checking host system type
configure result: x86_64-unknown-linux-gnu
configure checking for gcc
configure result: no
configure checking for cc
configure result: no
configure:4036: checking for cl.exe
configure:4066: result: no
configure:4090: error: in `/tmp/linux-nrpe-agent/subcomponents/nagiosplugins/nagios-plugins-2.2.1':
configure:4093: error: no acceptable C compiler found in $PATH
See `config.log' for more details.

Did you install the dev tools, prior to running the installer script?

Hi
I am still working on this agent install but can you tell me besides the installing the Dev Tools
and modifying the script is there anything else that should be installed ?

What are the packages (rpms) require to configure monitory on Redhat8 servers

Thanks

You don't need anything else. Once the dev tools is installed, you should have a compiler, and the Linux agent should install. The Linux agent consists of NRPE daemon and Nagios pluings. This is all you need to start monitoring your client machine.