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Sensu Docker Setup Documentation: Simplified Monitoring and Observability with Containerized Deployment

Sensu Docker Setup Documentation: Simplified Monitoring and Observability with Containerized Deployment

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Mahira Technology Private Limited
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Introduction :-

Sensu is a powerful open-source monitoring and observability tool that helps in monitoring various components of a system, such as servers, applications, and services. It can be run as a containerized application using #Docker, which provides an easy and efficient way to deploy and manage Sensu. In this blog post, we will walk through the steps to set up Sensu on #Docker.

Pre-Requestisites :-

  • #Docker should be installed on your local system

Step 1: Pull the #Docker Image

The first step is to pull the Sensu #Docker image from #Docker Hub. This can be done using the following command:

docker pull sensu/sensu

Note: If you encounter any permission issues, you may need to use the sudo command.

Step 2: Configure and Start

After pulling the Sensu #Docker image, we can configure and start the Sensu container using the following command:

docker run -v /var/lib/sensu:/var/lib/sensu \
-d - name sensu-backend \
-p 3000:3000 -p 8080:8080 -p 8081:8081 \
-e SENSU_BACKEND_CLUSTER_ADMIN_USERNAME=<username> \
-e SENSU_BACKEND_CLUSTER_ADMIN_PASSWORD=<password> \
sensu/sensu:latest \
sensu-backend start - state-dir /var/lib/sensu/sensu-backend - log-level debug

Let’s break down the above command:

  1. docker run -v /var/lib/sensu:/var/lib/sensu: This command creates a new container using the #Docker engine. The -v option is used to specify a volume to be mounted inside the container, allowing data to be shared between the host machine and the container. In this case, it is mounting the directory /var/lib/sensu on the host machine to the directory /var/lib/sensu inside the container.

  2. -d --name sensu-backend: These options run the container in detached mode and give it a name for easy reference.

  3. -p 3000:3000 -p 8080:8080 -p 8081:8081: These options map the container's ports to the corresponding ports on the host machine. This allows external processes to communicate with the container using these ports. Specifically, port 3000 inside the container is mapped to port 3000 on the host machine, port 8080 inside the container is mapped to port 8080 on the host machine, and port 8081 inside the container is mapped to port 8081 on the host machine.

  4. -e SENSU_BACKEND_CLUSTER_ADMIN_USERNAME=<username> -e SENSU_BACKEND_CLUSTER_ADMIN_PASSWORD=<password>: These environment variables allow us to specify the username and password for the Sensu backend cluster admin.

  5. sensu/sensu:latest: This is the name of the #Docker image that the container is based on. In this case, it is the sensu/sensu image with the latest tag, which is the most recent version of the image.

  6. sensu-backend start --state-dir /var/lib/sensu/sensu-backend --log-level debug: This is the command that is run inside the container when it starts up. It starts the Sensu backend process with the start command, and passes it the --state-dir and --log-level options to configure its behavior. The --state-dir option sets the directory where the backend process will store its state data, and the --log-level option sets the level of detail for log messages generated by the backend process.

Step 3 : Make a Request to the /health API

Before we dive into installing sensuctl, let’s make sure that our Sensu instance is up and running. You can do this by making a request to the /health API endpoint. Using the curl command-line tool, you can run the following command:

curl http://127.0.0.1:8080/health

This will send an HTTP request to the local web server running on your host machine at 127.0.0.1:8080. If you need administrative privileges to run the curl command, you can use sudo, like this:

sudo curl http://127.0.0.1:8080/health

Step 4: Install sensuctl

To start managing Sensu resources with sensuctl, you’ll need to install it first. Sensuctl is available as a package that can be installed on your system. Here’s how you can do it:

# Add the Sensu repository
curl -s https://packagecloud.io/install/repositories/sensu/stable/script.deb.sh | sudo bash

# Install the sensu-go-cli package
sudo apt-get install sensu-go-cli

This will add the Sensu repository to your system and install the sensu-go-cli package.

Step 5: Managing Containers

Once you have sensuctl installed, you can use it to manage various Sensu resources, such as events, entities, and more. For example, you can use sensuctl to manage containers running in your Sensu environment. To list all the running containers, you can run the following command:curl -s https://packagecloud.io/install/repositories/sensu/stable/script.deb.sh | sudo bash

docker run ps -a

This will provide you with a list of all the running containers in your Sensu environment, allowing you to easily manage and monitor them using sensuctl.

Step 6: Accessing Sensu Web UI

Sensu also provides a web-based user interface (UI) that you can access in your browser. Once your Sensu instance and containers are up and running, you can simply copy and paste the following URL in your browser:

http://localhost:3000

This will take you to the Sensu login page, where you can enter your credentials and access the web UI for managing your Sensu resources in a graphical way.

You can see the dashboard as below:

Conclusion :-

Using sensuctl, the official CLI for Sensu, you can easily manage resources such as events, entities, and containers in your Sensu environment. By making requests to the Sensu API, installing sensuctl, and accessing the web UI, you can efficiently manage and monitor your Sensu resources for effective observability.

Sensu DockerDockerDevopscontainerizationobservabilitydeploymentmonitoring toolmonitoringsetup