Docker

Docker is a #202204071114 technology that exposes its API in order to work with the containers. It utilises the Linux Container (LXC)# container technology. Lately, it also integrates WASM as a light alternative to LXC.

An installed package of Docker commonly consists of three parts:

Docker has a layered architecture where each layer could be reused for different containers. It mainly consists of two main layers: container layer and image layer. See 202110201654# for more details.

To build a Docker container, it generally needs two files:

Docker stores its information in /var/lib/docker. Its directory structure looks like the following: 

/var/lib/docker/:
  aufs/
  containers/
  image/
  volumes/

On the above, aufs could be any running storage driver supported by 202203251354# that store its information. containers stores information about #202204071114. image stores information about 202202211632#. volumes store any 202203251354#.

Links to this page
  • Server Templating
  • Red Hat Ansible Automation Platform

    Red Hat Ansible Automation Platform provides 202204272021# automation, cloud services , and content in 202204300837# which includes infrastructure like 202204081225#, cloud or container technologies (202110201636# and 202201291535#), network (CISCO) and security including devices and how they fit in the environment.

  • Namespace Isolation

    Namespace Isolation is a technique used by #Docker in order to isolate the running containers from the main operating system which at the same time does not alter the mechanism used to allocate the resources for processes.

  • Kubernetes

    Kubernetes is a #202203291434 tools which help manage containerised applications that could scale up to thousands of microservices. It is usually used alongside with other container technologies such as #202110201636.

  • Docker Swarm

    Docker Swarm is a #202203291434 tool designed for #202110201636.

  • Docker Service

    #202110201636 Service could be helpful on managing an application across multiple Docker hosts. It plays an important role in Docker’s 202203291434#.

  • Docker Registry

    #202110201636 Registry is a central repository for images just like GitHub. You could run docker push or docker pull to put or get the images from specified repository. By default, the images are push or pull from Docker Hub (docker.io).

  • Docker Networking

    The default network structure in #Docker is bridge or could be understood as Docker host’s internal network. Such network is private to the public which means that we need to map the port of the Docker container to the Docker host’s port where the clients will access. This could be done by adding the option -p {client-access-port}:{app-listen-port} to docker run.

  • Docker Image

    #202110201636 Image is simply a template for building #202203281423. It simplifies the software deployment in Linux distributions by the DevOps.

    There are various #202110201636 commands that interact with the Docker Image.

  • Docker Container

    Docker Container is a running instance of a 202202211632#. There are various 202110201636# commands that interact with the 202204071114#.

    Upon running, #202110201636 will create a layer on top of image layer (describe in #202110201654). The changes of file which located in image layer will be done in #202203251058 where all the changes will happen in container layer.

  • Docker CLI

    Docker CLI is used to access #202110201636 REST API. It could be done within a local host or from a remote client. Run docker run -H={ip-addr}:{port} if you are accessing a Docker host remotely.

  • Container Orchestration

    Container Orchestration is a technology that used alongside with container technology such as #202110201636 where it automates the management of containers across multiple systems as we called as cluster. It usually supports clustering, scaling, advance networking within cluster and auto-replacement of dead containers.

  • Application Container
#container #devops