How to Install Nagios Monitoring Tool

1. Updating the packages

• 2. Installing the latest version of Nagios XI

Note: You need a blank ubuntu lab before you proceed with installations. Any pre-installed tool/package might interfere with the installation process giving errors. So kindly, terminate the lab access and launch a fresh lab instance before you proceed with this demo.

1.1 Update the packages using the following command:

 sudo apt update -y 

• 2.1 Login as the root user using the command given below

 sudo -i
 

• 2.2 Execute the below command to install Nagios XI

curl https://assets.nagios.com/downloads/nagiosxi/install.sh | sh

Note: The installation takes around 20 mins. Please wait patiently till you get the Installation Complete message as shown below

• 2.3 Navigate to the user interface by using the URL provided in your terminal session. You can refer to the screenshot given above.

• 2.4 You will be presented with the Nagios XI Installation screen as shown below

• 2.5 You will be first prompted to define the General System Settings

• 2.6 Once you've made your desired selections choose your License Settings. Here for demonstration purposes we have chosen a trial version.

• 2.7 You will have to enter a key for the trial version. To get the key, click on the click to get a trial key link. You will be asked to enter details like the first name, last name and email id. Once you enter all those you will get the key mailed to the email-id you just mentioned. Enter the key as shown below

• 2.8 Click Next to proceed.

• 2.9 The next page provides you with options for the Admin Account. You can use the default password or change it if you want. After this click on Finish Install

• 2.10 The page will display a spinning logo while it applies your settings to Nagios XI.

• 2.11 The Installation Complete screen will be shown with the username and password required to login to Nagios XI.

• 2.12 Click the Login to Nagios XI button to begin.

• 2.13 The Login Screen will appear, provide your credentials and then click the Login button.

• 2.14 You will need to accept the License Agreement to proceed.

• 2.15 You will be logged into Nagios XI and be placed at the home screen.

Adding Hosts to the Nagios Monitoring Tool

1. Logging into the Nagios XI Dashboard

• 2. Adding a host using the core config manager

1.1 Login to the nagios dashboard using the url as mentioned in the previous demo.

• 2.1 Navigate to Configure > Core config manager from the nagios dashboard

• 2.2 To manually add a new host, select the Hosts link located under Monitoring on the left menu of CCM

• 2.3 This will bring up the Host Management page, which displays a list of the current hosts being monitored by Nagios XI.

• 2.4 Click the Add New button to manually add a new host.

• 2.5 The Host Management page will open on the Common Settings tab.

• 2.6 Define the primary host parameters such as Host Name, Description, Address, and Display name.

• 2.7 Use the Manage Parents button to associate parent host(s) for the host.

• 2.8 Use the Manage Templates button to associate template(s) to the host.

• 2.9 Use the Manage Host Groups button to associate existing host group(s) to the host

• 2.10 On the previous screenshot of the Common Settings tab you'll notice that the Active checkbox is checked. If this box is unchecked the host configuration won't be put into production when Apply Configuration is performed. However the settings will remain in CCM until you activate the host object.

• 2.11 To define the check command for this host, you select the appropriate command from the Check command drop down list . Every command in the Check command drop down list is associated with a set of Nagios Core commands and arguments, which are shown in the Command view field.

• 2.12 The Check Settings tab allows you to specify the settings for frequency of checks and also the host state

• 2.13 Configure settings as shown in the screenshot below

• 2.14 The Alert Settings tab allows you to specify your notification settings.

• 2.15 Enter the value as shown below:

• 2.16 Click on manage contacts to add any contact that needs to be notified about the host status.

• 2.17 The Misc Settings tab is for defining additional host information

• 2.18 Once you've finished entering information for your new host, click the Save button to return to the Host Management page

• 2.19 Click the Apply Configuration button to restart Nagios XI and put the new settings info effect. Nagios XI will verify the settings and display a success message that the host was set up correctly

• 2.20 You can see the apply configuration successful message as shown below:

• 2.21 You can verify that the host is added to the monitoring tool.

Continuous Monitoring on Docker with ELK Stack

1. Set up ELK stack on Docker
2. Configure Jenkins pipeline for Docker build and deployment
3. Run the Spring Boot application and check the logs in Kibana

1.1 Download Docker compose file in one of the git repositories and follow the set of commands given below to initialize the ELK stack.

 su
git clone https://github.com/Siraj-ul-muneera/ELKExample.git
cd ELKExample
ls -alrt
 

1.2 Start the ELK stack using the docker-compose command. Usually, this binary is not installed on a server. So, follow the set of commands given below to install Docker Compose.

 apt install docker-compose
docker-compose version
 

1.3 Before starting the ELK stack, run the command given below so that elastic search is configured properly.

 
sysctl -w vm.max_map_count=262144

1.4 Run the docker-compose command to initialize the ELK stack.

 docker-compose up -d
docker ps

1.5 Open the Kibana URL using the public IP of the host and 5601 port to access the Kibana dashboard.

http://localhost:5601/app/kibana

• 2.1 From the browser, navigate to http://localhost:8080 and login to Jenkins.

• 2.2 Configure your Docker hub credentials in Jenkins. Go to Manage Jenkins -> Manage Credentials -> click on Jenkins link -> click on Global credentials (unrestricted) -> click on Add Credentials from the left pane.

• 2.3 Add the details as shown below

 Username: <Your_DockerHub_Username>
Password: <Your_DockerHub_Password>
 

• 2.4 You should now see the credentials saved as shown below

• 2.5 Create a Jenkins pipeline job to fetch Jenkinsfile from the URL mentioned below.

• 2.6 You can either use the below git repository or Fork it in your Github account and use it https://github.com/Siraj-ul-muneera/ELKExample.git

• 2.7 Configure the job as shown in the screenshot below and then run the build.

• 2.8 Give 777 permission to the Docker sock file since we are running Docker command from a Jenkins user.

 chmod 777 /var/run/docker.sock

• 2.9 Build the Jenkins job to deploy the Docker container on the Docker host.

• 2.10 Jenkins pipeline will complete the build and the deployment process for the Spring Boot application

• 2.11 We can see the Docker container deployed on the Docker host using the command:

 docker ps | grep springbootapp

3.1 Access the Spring Boot web application and perform some random activity so that the logs will be pushed to ELK stack.

http://localhost:81

3.2 Check the logs pushed to ELK stack in Kibana.

3.3 Navigate to the Kibana dashboard. Select Management > Index Management from the navigation bar on the left. You can see the logs created.