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Container Cpu Limit Configuration

Wed, 01 Jul 2026 13:30:50 +0000

Introduction

In this lab, you’ll limit the CPU usage of a Docker container that consumes excessive CPU resources.

Scenario

A container named cpu_test is running from the myapp:cpu image and performs CPU-intensive computations. When monitored with docker stats, the container regularly consumes 150–200% CPU, utilizing multiple CPU cores and impacting other services on the host.

Task

Recreate the container with a CPU limit of 500m CPU so that docker stats reports CPU usage consistently below 60% during validation.

Docker Compose Basic

Wed, 01 Jul 2026 11:38:29 +0000

Introduction

In this lab, you’ll first deploy an application by setting up network, multiple containers individually. Then you will clean up resources, and deploy the same application using Docker Compose.

Task 1: Create a Bridge Network

Create a bridge network named clicknet.

 
 BASH
 
docker network create --driver bridge clicknet

Verify

list docker networks

$ docker network ls
NETWORK ID NAME DRIVER SCOPE
5aa54ade2dcc bridge bridge local
fc40bfcbce91 clicknet bridge local
238b23f4e2a9 host host local
59b9cbf97489 none null local

Task 2: Run a Redis Container

Create a background container named redis using the redis:alpine image and attach it to the clicknet network.

Docker Environment Variables and Networking

Tue, 16 Jun 2026 06:50:38 +0000

In this lab, we’ll explore:

Inspecting environment variables in running containers
Passing environment variables at runtime
Deploying MySQL containers
Creating custom Docker networks
Connecting applications and databases across containers

Task 1: Inspect Environment Variables

First, identify the value configured for the APP_COLOR environment variable in a running container.

List the running containers:

$ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
cdf886f902d4 kodekloud/simple-webapp "python app.py" 10 minutes ago Up 10 minutes 8080/tcp mystifying_knuth

Inspect the container and look for the Env section:

Docker Basic Commands

Mon, 01 Jun 2026 12:33:56 +0000

Task 1

What is the version of the Docker Server Engine running on the host?

Check Docker version

$ docker version

Client:
Version: 25.0.5
API version: 1.44

Server:
Engine:
Version: 25.0.5
API version: 1.44

Answer: 25.0.5

Task 2

How many containers are currently running on this host?

List running containers

$ docker ps

CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES

Answer: 0

Task 3

How many images are available on this host?

Publishing Ports in Docker

Fri, 01 May 2026 14:37:01 +0000

Task

Solution

Show solution

This is the first paragraph of detailed content. This is the second paragraph of even more detailed content.

You can also include lists
Or other markdown elements

 
 service/networking/network-policy-default-deny-egress.yaml
 
 

 
 
---
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
 name: default-deny-ingress
spec:
 podSelector: {}
 policyTypes:
 - Ingress

 
 BASH
 
ls -R /etc/
grep "name" file.txt

 
 PYTHON
 
name = "God"
greeting = f"Hello {name}"
print(greeting)

Terminal output

Before

Docker failed to resolve

Tue, 31 Mar 2026 05:27:57 +0000

I recently enountered this error.