Using Container Like A Boss

Containers are the fundamental building blocks of Docker tool-kit. Before we get stared, we have to make sure the latest version of Docker is installed in the system. It is important to keep in mind, Docker is different from the VM.

In this article, we are going to discuss, how Docker is different from VM, play with Nginx server container and look into basic networking of Docker.

Before we dive, let's check the Docker Version in our system.

docker version

With this command, we should get an output, something like this,

Client: Docker Engine - Community
 Version:           20.10.5
 API version:       1.41
 Go version:        go1.13.15
 Git commit:        55c4c88
 Built:             Tue Mar  2 20:18:20 2021
 OS/Arch:           linux/amd64
 Context:           default
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          20.10.5
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.13.15
  Git commit:       363e9a8
  Built:            Tue Mar  2 20:16:15 2021
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.4.4
  GitCommit:        05f951a3781f4f2c1911b05e61c160e9c30eaa8e
 runc:
  Version:          1.0.0-rc93
  GitCommit:        12644e614e25b05da6fd08a38ffa0cfe1903fdec
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

If you get the Docker server information, that means we can talk to the server. Otherwise, there is something wrong with the Docker installation, like not installed properly, having permission error etc.

Since, we are going to a lot of new features, ideally you should get the latest version as possible.

Additionally, to get more information about the installed Docker server, we can run,

docker info

Commands and Management Commands

If we want to look all the available commands for Docker, we can run,

docker

From this output, we can notice two sections

1. Management Commands
2. Commands

Previously, all the Docker commands was available like docker command. Since the number of commands increase, the Docker team decided to separate them in sum-commands aka Management Commands. With Management Commands, we run commands like docker <command> <sub-command>.

Old Way: docker <command> (options)

New Way: docker <command> <sub-command> (options)

All the old commands are working fine with latest Docker. But Docker is pushing forward to use the new model Management Command.

Image Vs Container

An image is an application we want to run. On the other hand, a Container is an instance of the image. Essentially, we can have multiple container running of the same image.