1: Install Required Packages and Dependencies.
We assume that you have fresh installed CentOS, Red hat or Fedora systems, So our first requirement is to install Apache and PHP first. Use the following commands to complete it. You can find detailed LAMP setup instruction here.
Install Packages:
# yum install httpd php php-cli gcc glibc glibc-common gd gd-devel net-snmp openssl-devel make
yum install -y gcc glibc glibc-common gd gd-devel make net-snmp openssl-devel
2: Setup User Accounts,
Now create a new nagios user account and setup a password to this account.
# useradd nagios
# passwd nagios
Now create a groud for nagios setup “nagcmd” and add nagios user to this group. Also add nagios user in apache group.
# groupadd nagcmd
# usermod -a -G nagcmd nagios
# usermod -a -G nagcmd apache
3: Install Nagios Core Service.
After installing required dependencies and adding user accounts. Lets start with Nagios core installation. Download latest nagios core service from official site.
# cd /opt/
# wget http://prdownloads.sourceforge.net/sourceforge/nagios/nagios-4.0.8.tar.gz
# tar -xf xxxx.tar.gz
# cd xxx
# ./configure --with-command-group=nagcmd
# make all
# make install
# make install-init
# make install-config
# make install-commandmode
Now use below command to setup apache configuration for Nagios installation.
# make install-webconf
4: Configure Apache Authentication.
We need to setup apache authentication for user nagiosadmin. Do not change this username. else you would required more changes in configuration.
# htpasswd -c /usr/local/nagios/etc/htpasswd.users <usernmae>
Now restart Apache service to make the new settings take effect.
# service httpd restart
5: Install Nagios Plugins.
After installing and configuring Nagios core service, Download latest nagios-plugins source and install using following commands.
# cd /opt
# wget http://nagios-plugins.org/download/nagios-plugins-2.0.3.tar.gz
# tar xzf nagios-plugins-2.0.3.tar.gz
# cd nagios-plugins-2.0.3
Now compile and install nagios plugins
# ./configure --with-nagios-user=nagios --with-nagios-group=nagios
# make
# make install
6: Verify and Start Nagios
Use the following commands to verify nagios install and start nagios core service.
# /usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg
# service nagios start
Also configure nagios service to start on system start.
# chkconfig --add nagios
# chkconfig nagios on
7: Access Nagios in Web Browser.
Nagios creates its own apache configuration file /etc/httpd/conf.d/nagios.conf. There are no need to make any changes to it. Simply open below url in browser.
[change domain name with your domain or ip]
http://<ip address>/nagios/
NRPE Installation in nagios-server
1. Download the source code tarball of the NRPE addon (visit http://www.nagios.org/download/ for links to the latest
versions). At the time of writing, the latest version of NRPE
# wget wget http://downloads.sourceforge.net/project/nagios/nrpe-2.x/nrpe-2.15/nrpe-2.15.tar.gz
2.Extract the NRPE source code what your downloaded.
# tar -xf nrpe-2.8.tar.gz
Move in to directory
# cd nrpe-2.8
3.Compile the NRPE addon.
# ./configure
# make all
5.Install the NRPE plugin.
# make install-plugin
6. Test communication with the NRPE daemon.
Make sure the check_nrpe plugin can talk to the NRPE daemon on the remote host. Replace "192.168.0.1" in the
command below with the IP address of the remote host that has NRPE installed.
# /usr/local/nagios/libexec/check_nrpe -H 192.168.0.1
7.write command in commands.cfg file
define command{
command_name check_nrpe
command_line $USER1$/check_nrpe -H $HOSTADDRESS$ -c $ARG1$}