Skip to content

Contact sales

By filling out this form and clicking submit, you acknowledge our privacy policy.
  • Labs icon Lab
  • A Cloud Guru
Google Cloud Platform icon
Labs

Configure Nagios Core for Log Monitoring

No matter how well we set up our infrastructure, eventually something will go wrong that needs to be fixed. When that happens, the first step is to check the logs for errors and warnings. In this hands-on lab, we will create a Nagios service that monitors the logs for errors and warnings using the `check_log` plugin.

Google Cloud Platform icon
Labs

Path Info

Level
Clock icon Intermediate
Duration
Clock icon 1h 0m
Published
Clock icon Jul 19, 2019

Contact sales

By filling out this form and clicking submit, you acknowledge our privacy policy.

Table of Contents

  1. Challenge

    Define Two Command Objects that Check the Logs **/var/log/messages** for Errors and Warnings in **/usr/local/nagios/etc/objects/commands.cfg**

    1. Add the following text to the commands.cfg file:

      define command {
      
              command_name    check_log_error
              command_line    /usr/local/nagios/libexec/check_log -F /var/log/messages -O /home/nagios/check_log.error -q "error"
      
      }
      
      
      define command {
      
              command_name    check_log_warning
              command_line    /usr/local/nagios/libexec/check_log -F /var/log/messages -O /home/nagios/check_log.warning -q "warning"
      
      }
      
      
  2. Challenge

    Define Two Services that Use the Commands

    1. Add the following text to the localhost.cfg file:

      define service {
      
              use                     local-service
              host_name               localhost
              service_description     Check Log Error
              check_command           check_log_error
      
      }
      
      define service {
      
              use                     local-service
              host_name               localhost
              service_description     Check Log Warnings
              check_command           check_log_warning
      
      }
      
  3. Challenge

    Give the `nagios` User Read Permissions for `/var/log/messages`

    1. Run the following command:
    sudo setfacl -R -m u:nagios:r-- /var/log/messages
    
  4. Challenge

    Restart and Log In to the Nagios Server

    1. Restart the Nagios server.
    sudo systemctl restart nagios
    
    1. Navigate to http://NAGIOS_SERVER_IP/nagios, and log in with the following credentials:
      • User Name: nagiosadmin
      • Password: BlaBla321
    2. Navigate to Services.
    3. Reschedule the checks for the two services to run 10-20 seconds from the current server time.
    4. Verify that there are no errors under Status Information.

The Cloud Content team comprises subject matter experts hyper focused on services offered by the leading cloud vendors (AWS, GCP, and Azure), as well as cloud-related technologies such as Linux and DevOps. The team is thrilled to share their knowledge to help you build modern tech solutions from the ground up, secure and optimize your environments, and so much more!

What's a lab?

Hands-on Labs are real environments created by industry experts to help you learn. These environments help you gain knowledge and experience, practice without compromising your system, test without risk, destroy without fear, and let you learn from your mistakes. Hands-on Labs: practice your skills before delivering in the real world.

Provided environment for hands-on practice

We will provide the credentials and environment necessary for you to practice right within your browser.

Guided walkthrough

Follow along with the author’s guided walkthrough and build something new in your provided environment!

Did you know?

On average, you retain 75% more of your learning if you get time for practice.

Start learning by doing today

View Plans