Introduction:

• It is an open source monitoring software like cloudwatch in AWS.

Installation: Nagios_server or Local Host

• Create an AWS ubuntu instance: Nagios_server
  • security group open the following ports:
    • Custom TCP   0-65535       Anywhere
    • HTTP                     80        Anywhere
    • Open ICMP V4    echoReply  Anywhere
  • #sudo apt-get update
  • #sudo apt-get install nagios3- popup will appear, select following
    • postfix configuration: use tab and ok
    • general type of mail configuration: internet site: ok
    • system mail name: nagios_server: ok
    • Nagios web administration password: India123
    • To check nagios is installed: copy AWS instance public DNS & paste in browser: ec2-3-9-174-109.eu-west-2.compute.amazonaws.com/nagios3
    • Default username: nagiosadmin, password: India123 (during installation)
  • in nagios3 dashboard, select services: it will display current network status of nagios_server or local host.

Add Remote servers to Nagios3:

• To add any remote server to which perform monitoring through nagios server.
  • #sudo vi /etc/nagios3/nagios.cfg
  • check_external_command=1 (in Line 145 change 0 to 1, save & Exit)
  • #sudo vi /etc/group
  • add nagios:x:118:www.data (in line58, save & Exit)
  • #sudo chmod g+w /var/lib/nagios3/rw
  • #sudo chmod g+w /var/lib/nagios3
  • #sudo service apache2 restart
  • #sudo service nagios3 restart
• create a new config file for each remote servers.
  • #sudo vi /etc/nagios3/conf.d/    #ls (display all .cfg files)
  • create a new file for remote server (nagios_remote_server1) for more details: https://www.theurbanpenguin.com/nagios-defining-a-new-host/
    • #sudo vi nagios_remote_server1.cfg
    • copy and paste the following. and change the host_name , alias , address ( private_ip )

    • define host { host_name ec2-3-8-137-244.eu-west-2.compute.amazonaws.comec2-3-8-137-244.eu-west-2.compute.amazonaws.com alias store nagios_remote_server1 address max_check_attempts 3 check_period 24x7 check_command check-host-alive contacts root notification_interval 60 notification_period 24x7 }

  • Restart nagios3
    $ sudo /etc/init.d/nagios3 restart
  • Go to nagios home page and refresh
    select host groups
    We can see the new host.