I currently have Icigna 1.2 (classic, web, and mobile) running on Ubuntu 10.10. I have a few other Linux servers that I would like to monitor as well. There is a good amount of information on installing Nagios and things to accompany it but Icigna documentation and blogs are fewer.
The goal of this post is to document how to install NRPE on a Icinga server (Ubuntu 10.10 x64) and monitor a remote host (CentOS 5.5 x64).
I also want to give credit to two other blog posts I used to get my systems functional and for this post.
fishfood: http://www.fishfood.co.nz/2010/03/howto-install-nagios-nrpe-for-use-with.html
The Geek Stuff: http://www.thegeekstuff.com/2008/06/how-to-monitor-remote-linux-host-using-nagios-30/
Remote Host
Install Dependencies:
yum install openssl-devel.x86_64 xinetd
Create user and assign password
useradd icinga && passwd icinga
Install Nagios plugins
cd /usr/src
wget http://downloads.sourceforge.net/project/nagiosplug/nagiosplug/1.4.15/nagios-plugins-1.4.15.tar.gz
tar xzvf nagios-plugins-1.4.15.tar.gz
cd nagios-plugins-1.4.15
./configure --prefix=/usr/local/icinga --with-nagios-user=icinga --with-openssl=/usr/bin/openssl
make && make install
Change permissions on the plugin directories
chown icinga.icinga /usr/local/icinga
chown -R icinga.icinga /usr/local/icinga/libexec
Now we move to installing NRPE. Change directories to /usr/src (or wherever you want to store your download) and download the archive.
cd /usr/src
wget http://prdownloads.sourceforge.net/sourceforge/nagios/nrpe-2.12.tar.gz
Extract the files and enter directory
tar -zxvf nrpe-2.12.tar.gz && cd nrpe-2.12
Compile & install
./configure --with-nrpe-user=icinga --with-nrpe-group=icinga --with-nagios-user=icinga --with-nagios-group=icinga --enable-ssl --libexecdir=/usr/local/icinga/libexec/ --bindir=/usr/local/icinga/bin/
make all
make install-plugin
make install-daemon
make install-daemon-config
make install-xinetd
On the 2nd to last line where it says "only_from = 127.0.0.1" add the IP of your Icinga server so that it would look like "only_from = 127.0.0.1 192.168.0.200" where 192.168.0.200 is your Icinga server.
nano /etc/xinetd.d/nrpe
Edit services file
nano /etc/services
Then press CTRL+W then CTRL+V to jump to the last line and add the following line above # Local services
nrpe 5666/tcp # NRPE
Enable Xinetd to boot at startup, start, and restart the service
chkconfig xinetd on
service xinetd start && service xinetd restart
Check to see if the port is open, the output should be "tcp 0 0 *:nrpe *.* LISTEN"
netstat -at |grep nrpe
Check if NRPE is functioning locally, the output should be "NRPE v2.12"
/usr/local/icinga/libexec/check_nrpe -H localhost
If you are running iptables on this remote host you will need to open port 5666 from your Icinga server.
iptables -I RH-Firewall-1-INPUT -p tcp -m tcp --dport 5666 -j ACCEPT
Save your iptables configuration
iptables-save
Edit NRPE Config File
nano /usr/local/nagios/etc/nrpe.cfg
Add the following lines under the existing command[] lines. This will allow you to monitor the sda1 partition and / partition in a LVM environment.
command[check_sda1]=/usr/local/icinga/libexec//check_disk -w 20% -c 10% -p /dev/sda1
command[check_part1]=/usr/local/icinga/libexec/check_disk -w 20 -c 10 -p /
Host Setup
This is for an Ubuntu/Debian based server. Start by installing the following dependcy.
sudo apt-get install libssl-dev
Download and extract NRPE
cd /usr/src
sudo wget http://downloads.sourceforge.net/project/nagios/nrpe-2.x/nrpe-2.12/nrpe-2.12.tar.gz
sudo tar zxvf nrpe-2.12.tar.gz && cd nrpe-2.12
Compile & Install
sudo ./configure --with-nrpe-user=icinga --with-nrpe-group=icinga --with-nagios-user=icinga --with-nagios-group=icinga --enable-ssl --libexecdir=/usr/local/icinga/libexec/ --bindir=/usr/local/icinga/bin/
sudo make all && sudo make install
Check to see if you can contact the remote host you just setup.
sudo /usr/local/icinga/libexec/check_nrpe -H 192.168.0.100
Create A Host
I use individual files for my hosts, below is a template that I used to monitor a remote host. It is pretty basic at the moment and I would like to add more in the future but that will have to be another article.
###############################################################################
###############################################################################
#
# HOST DEFINITIONS
#
###############################################################################
################################################################################ Define a host for the Windows machine we'll be monitoring
# Change the host_name, alias, and address to fit your situationdefine host{
use corp-servers ; Inherit default values from a template
host_name YourHostName ; The name we're giving to this server
alias YourHostName ; A longer name for the server
address 192.168.0.100 ; IP address of the server
}###############################################################################
###############################################################################
#
# SERVICE DEFINITIONS
#
###############################################################################
###############################################################################define service{
use generic-service
host_name YourHostName
service_description CPU Load
check_command check_nrpe!check_load
}
define service{
use generic-service
host_name YourHostName
service_description Current Users
check_command check_nrpe!check_users
}
define service{
use generic-service
host_name YourHostName
service_description / Free Space
check_command check_nrpe!check_part1
}
define service{
use generic-service
host_name YourHostName
service_description /boot Free Space
check_command check_nrpe!check_sda1
}
define service{
use generic-service
host_name YourHostName
service_description Total Processes
check_command check_nrpe!check_total_procs
}
define service{
use generic-service
host_name YourHostName
service_description Zombie Processes
check_command check_nrpe!check_zombie_procs
}
Once you have this file on your server, restart run a sanity check on your configurations and restart the service and you should have a functional host in Icinga now.
sudo /usr/local/icinga/bin/icinga -v /usr/local/icinga/etc/icinga.cfg
sudo /etc/init.d/icinga restart
Src: http://www.deobfuscate.net/?p=680
