Home » DevOps


Docker Swarm Tutorial

1. Introduction This post introduces Docker Swarm – the Docker Engine’s Swarm mode. The Swarm mode enables multiple machines running Docker Engines to collaborate in a cluster. Let us explore the basics of this. To follow the examples provided here you will need Docker Engine 1.12 or above to be installed in your machine. You will also need to install ...

Read More »

Jenkins Docker Image Example

1. Introduction In this post we will learn about how to install and configure Jenkins through the Jenkins Docker image. This is the official Docker image of Jenkins available from the Docker hub here. Please ensure that you have Docker engine and Docker-Compose installed to try out the examples provided in this post. 2. Install Jenkins Docker Image The official ...

Read More »

Docker Environment Variables Example

1. Introduction In this post, we will discuss different ways to pass and set environment variables into a Docker container. Typically, when a new container is created Docker assigns it a few environment variables by default like so: $ docker run alpine:latest env PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin HOSTNAME=de2c993a62fb HOME=/root Let us now explore what options do we have to inject our custom environment ...

Read More »

Docker Container Networking Tutorial

1. Introduction In this post, we will learn the basics of Docker container networking in a single host setup. We will see the basic inrastructure provided by the Docker Engine for container networking, the “Docker network” family of commands, and the basics of creating user-defined networks. We wil not cover networking with containers in multiple hosts setup here. 2. Docker ...

Read More »

Docker Kernel Requirements

1. Introduction Docker is a containerization technology that provides OS level virtualization to applications.  It isolates processes, storage, networking, and also provide security to services running within it’s containers.  To enable this, Docker depends on various features of the Linux Kernel.  Let us get introduced to these Docker kernel requirements in this post. 2. Docker engine dependencies from the Linux ...

Read More »

Configuring DNS in Docker

1. Introduction This post introduces Docker Engine’s network feature in general and specifically introduces configuring DNS in containers. This post assumes that you have the Docker Engine installed and that you know the basics of working with containers. We will not discuss service discovery from other networks here since that needs a deeper knowledge of Docker tools like Docker Swarm. ...

Read More »

Docker as a Service

In the previous posts we learned about Docker, containers, and working with containers, In this post we will learn about Containers as a Service (CaaS) in general and how Docker realizes CaaS. 1. Why Docker as a Service? Take a typical developer work-flow involving Docker. It will be typically as below. This is based on the reference workflow provided in ...

Read More »

Docker List Containers Examples (docker ps)

1. Introduction In this post we will explore the command docker ps which is used to list Docker containers. We will also explore the various options of this command.  This tutorial assumes that you have a working Docker installation.  If you are new to Docker please read how to install Docker and create containers before proceeding further. 2. Docker Container – It’s ...

Read More »

Connect to Docker Container Example

1. Introduction This example introduces how to create a Docker container and connect to it. The previous posts discussed creating basic Hello World containers and understanding your Docker installations. This post carries it further to talk about working with containers. This post assumes that you have a working Docker installation.  Let’s start 2. Understanding Docker container and image A Docker ...

Read More »

What is a Docker container – How to use Docker?

1. Introduction Containers, in general, and Docker in particular is quickly gaining in popularity.  In this post, we will get some basics sorted out about the Docker container.  We will learn the meaning of the term Container in general and see specifically how Docker implements them.  We will try to execute a few basic commands to understand the bare basics ...

Read More »

Want to take your Java skills to the next level?

Grab our programming books for FREE!

Here are some of the eBooks you will get:

  • Spring Interview QnA
  • Multithreading & Concurrency QnA
  • JPA Minibook
  • JVM Troubleshooting Guide
  • Advanced Java
  • Java Interview QnA
  • Java Design Patterns