Challenge, Medium,  on  Kubernetes

Why LimitRange Is Not Injecting Default Requests and Limits into Running Pods

Scenario

A LimitRange named range-delta is configured in the project-delta namespace with default CPU and memory requests and limits.

A Deployment named web-app is running 3 Pods in the same namespace. However, none of the Pods have CPU or memory requests and limits applied.

Investigate why the LimitRange is not injecting default limits and requests, and fix the issue without modifying the LimitRange configuration

Task

Find and fix the root cause of why LimitRange defaults are not being applied to Pods.

Ensure all Pods of web-app automatically receive the default resource requests and limits from range-delta.

⏳ Wait for about 1 minute for the environment to be fully set up.

⚠️ Do not modify the LimitRange or the Deployment.

Hint

SSH into the control plane node and inspect the kube-apiserver manifest:

/etc/kubernetes/manifests/kube-apiserver.yaml

Look for admission controller flags related to LimitRanger.

If it is disabled, adjust the configuration so that LimitRanger is active again.

Test Cases

How to Author Challenges on iximiuz Labs

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Install labctl CLI

curl -sf https://labs.iximiuz.com/cli/install.sh | sh

This will download and install the latest version of the labctl CLI. You only need to do this once per workstation.

Authorize labctl

labctl auth login

This will open a browser window asking you to authorize labctl to access your account. You need to do it after a fresh install of labctl and repeat it whenever the auth session expires.

Pull challenge content

labctl content pull challenge why-limitrange-not-injecting-default-requests-limits-running-pods-f82a1792

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Stream your changes

labctl content push -fw challenge why-limitrange-not-injecting-default-requests-limits-running-pods-f82a1792

Run this command in a separate terminal to continuously upload your changes to the server while editing the challenge in your favorite text editor or IDE.

You can also use labctl to create, list, and delete your content. Learn more about the available commands: labctl content --help

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