Install Monitoring Tool Nagios on RHEL,CentOS

I First step  :

Here i ll show you a way to install nagios monitoring tool.This installation has been tested by unixmen team in (Fedora ,Cenots, RHEL) and conjointly in my system

1- First   install some  tools :- httpd, gcc, glib, glibc-common, gd and gd-devel

 #yum install httpd php

 #yum install gcc

 #yum install glibc glibc-common

 #yum install gd gd-devel

2- Create  nagios  user :-

#/usr/sbin/useradd -m nagios

#passwd nagios

3- Add  nagcmd  group

#/usr/sbin/groupadd nagcmd

#/usr/sbin/usermod -a -G nagcmd nagios

#/usr/sbin/usermod -a -G nagcmd apache

4- Now you'll go to the link http://www.nagios.org and download the files

a) nagios-3.2.0.tar.gz  b) nagios-plugins-1.4.14.tar.gz 

#tar  -zxvf  nagios-3.2.0.tar.gz   (extract the package)

#cd  nagios-3.2.0  (enter the package)

#./configure --with-command-group=nagcmd

#make all; make install; make install-init; make install-config; make install-commandmode; make install-webconf

5-  Edit  your  email  admin address :

Go to

vi /usr/local/nagios/etc/objects/contacts.cfg

6- Create a nagiosadmin account for logging into the Nagios web interfaceassign to this you’ll need it later.

#htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin

enter   the  password.

7- Restart  the  httpd  server :

#Service  httpd   restart

The  second  step  : Extract   and  install  plugins

1- Go  to you  downloaded  nagios  tools

 #tar  -zxvf   nagios-plugins-1.4.14.tar.gz

2- cd  nagios-plugins

#./configure --with-nagios-user=nagios --with-nagios-group=nagios

make; make   install

3- Now  you  have  to  add nagios  to  Chkconfig

#chkconfig --add nagios

#chkconfig nagios on

4- Verify  if  you  have  a  good config of nagios with the command

#/usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg

5- Check if  there  are  no errors  displayed;  then start   nagios with command :

#service  nagios  start or /etc/init.d/nagios restart

6- Now we can that  You're Done
To simplify(alter) the procesure plz disable the selinux and iptables and  ip6tables

now open your browser and http://localhost/nagios or http://yoursystemipaddress/nagios

Troubleshoot

if it show some internal error then

#su - (To become Root User)

#setenforce  0 (Disable the Selinux)

#/etc/init.d/nagios restart (Restarting the service)

Now attempt it'll work :)

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