Use context: kubectl config use-context k8s-c1-H

The metrics-server has been installed in the cluster. Your college would like to know the kubectl commands to:

1. show Nodes resource usage
2. show Pods and their containers resource usage

Please write the commands into /opt/course/7/node.sh and /opt/course/7/pod.sh.

Monitoring Resource Usage in Kubernetes with kubectl top

Monitoring resource usage is crucial for maintaining a healthy and efficient Kubernetes cluster. In this guide, we’ll explore how to use the kubectl top command to view resource consumption, such as CPU and memory usage, for both nodes and pods.

Step 1: Understanding the kubectl top Command

The kubectl top command is used to display resource usage in a Kubernetes cluster. This command relies on the Metrics Server, which must be correctly configured and running in your cluster. You can see the available options by running:

This displays help information about the kubectl top command, showing the available options and usage examples. The two main subcommands are:

• node: Display resource usage of nodes.
• pod: Display resource usage of pods.

Step 2: Checking Node Resource Usage

To monitor the resource usage across all nodes in your cluster, use the following command:

This command provides an overview of CPU and memory usage for each node. For example:

This output shows the resource usage for each node, including the CPU and memory consumption as both absolute values and percentages.

To automate this monitoring, you can create a shell script:

Step 3: Checking Pod Resource Usage

Similarly, you can monitor the resource usage of individual pods using the following command:

The --containers=true flag includes container-level metrics within each pod. This is useful for detailed monitoring, especially in multi-container pods. The help command provides more details:

This output includes options for customizing the output, such as removing headers or specifying particular containers within a pod. To automate pod resource monitoring, create another script:

By using the kubectl top command, you can easily monitor the resource usage of nodes and pods in your Kubernetes cluster. This is vital for identifying resource bottlenecks and ensuring that your applications run smoothly.