Kubernetes is leading software in container orchestration. Kubernetes works by managing clusters, which is simply a set of hosts meant for running containerized applications. In order to have a Kubernetes cluster, you need a minimum of two nodes – a master node and a worker node. Of course, you can expand the cluster by adding as many worker nodes as you need.
docker
How to install Docker on Ubuntu 22.04
The purpose of this tutorial is to show how to install Docker on Ubuntu 22.04 Jammy Jellyfish Linux. Docker is a tool that is used to run software in a container. It’s a great way for developers and users to worry less about compatibility with an operating system and dependencies because the contained software should run identically on any system.
Change Docker root directory /var/lib/docker to another location
By default, Docker stores most of its data inside the /var/lib/docker directory on Linux systems. There may come a time when you want to move this storage space to a new location. For example, the most obvious reason might be that you’re running out of disk space.
How to connect to Docker container via ssh
After installing Docker on Fedora, AlmaLinux, Manjaro, or some other distro, it’s time to install more containers. Once you have a Docker container up and running on a Linux system, one of the things you’ll likely need to do is run commands inside the container. This allows you to use the container similarly to how you would a physical machine, except that Docker has done most of the setup legwork for us already.
There are already two commands available that allow us to run commands on a Docker container. The first one is docker exec, and the second command, which allows us to attach to a running container, is docker attach. These commands usually suffice, but you may find yourself in a scenario where you’d prefer to use SSH to connect to the Docker container and manage it.
Not all Docker containers are provisioned to run SSH. Normally, Docker containers are very lightweight and only programmed to do one thing. However, some Docker containers will allow SSH, and this can make management of the container much easier. In this guide, we’ll see how to connect to a Docker container via SSH from the host system on Linux command line.
In this tutorial you will learn:
- How to connect to a running Docker container via SSH
How to share data between a Docker container and host system using volumes
The easiest way to share data between a Docker container and the host system is to use Docker’s volumes. In this guide, we will go through the step by step instructions of sharing files between a Docker container and host system using Docker volumes via the command line on Linux.
Docker volumes work similarly to bind mounts, but are the preferred method for sharing data between a host system and Docker container because outside applications are not able to access the files and modify them.
In this tutorial you will learn:
- How to use volumes to share data between a Docker container and host system
Docker container: Backup and Restore
The purpose of this guide is to go over the step by step instructions of how to back up a Docker container on the Linux command line. We’ll also show how to restore a Docker container from backup. This can be done on any Linux system where Docker is installed, and will work on any Linux distribution.
To understand the Docker container backup and recovery process we first need to understand the difference between a Docker image and a Docker container. A Docker image contains an operating system with possibly one or more preconfigured applications, whereas a Docker container is a running instance created from an image.
In this tutorial you will learn:
- How to back up a Docker container on Linux
- How to restore a Docker container on Linux
Basic networking example on how to connect docker containers
One of the many desirable features built directly into Docker is networking. Docker’s networking feature can be accessed by using a --link flag which allows to connect any number of Docker containers without the need to expose a container’s internal ports to the outside world.
In this guide, you will learn how to network two or more Docker containers together on a Linux system through command line instructions. This will work on any Linux distribution. Check out the step by step instructions below to find out how.
In this tutorial you will learn:
- How to network Docker containers together
How to remove all docker containers using a single command
In this guide, we will show command line examples for removing all Docker containers from a Linux system. This will work on any Linux distribution.
Along with removing Docker containers, you’ll also learn how to remove Docker images, volumes, and networks. This is useful when you want to completely purge all traces of containers from your Docker installation and start fresh. Check out the examples below to find out how.
In this tutorial you will learn:
- How to list, stop, and remove all Docker containers
- How to remove Docker images, volumes, and networks
How to install Docker on Fedora Linux system
Docker is a tool that is used to run software in a container. It’s a great way for developers and users to worry less about compatibility with an operating system and dependencies because the contained software should run identically on any system.
Docker is available for download and installation on Fedora as well as most other distributions of Linux. However, installing it on Fedora can be a bit tricky because Red Hat doesn’t offer native support for Docker on its distributions. Instead, Red Hat pushes support for Podman, an alternative to Docker. This makes Docker a bit harder to install, but it’s still possible on Fedora.
In this guide, we’ll show you how to install Docker on Fedora and get started with installing containerized software. After Docker is installed, you can use it to install software packages much the same way you would use your distro’s package manager to download an app. The difference of using Docker is that everything is more automated, with compatibility and dependencies no longer being potential issues.
In this tutorial you will learn:
- How to install Docker
- How to start Docker and make it run automatically at boot
- How to run Docker without root
- How to search for a Docker image
- How to install a Docker image
- How to run a Docker image
- How to monitor Docker with various commands
- How to automatically start a Docker container
Install Docker on AlmaLinux
Docker is a tool that is used to run software in a container. It’s a great way for developers and users to worry less about compatibility with an operating system and dependencies because the contained software should run identically on any system.
If you’ve recently installed AlmaLinux or migrated from CentOS to AlmaLinux, you may be wondering how to get Docker up and running on the system. Unfortunately, Red Hat Enterprise Linux doesn’t offer native support for Docker, and neither does AlmaLinux, since it is a fork of RHEL. Instead, Red Hat pushes support for Podman, an alternative to Docker. This makes Docker a bit harder to install, but it’s still possible on AlmaLinux.
In this guide, we’ll show you how to install Docker on AlmaLinux and get started with installing containerized software. After Docker is installed, you can use it to install software packages much the same way you would use your distro’s package manager to download an app. The difference of using Docker is that everything is more automated, with compatibility and dependencies no longer being potential issues.
In this tutorial you will learn:
- How to install Docker
- How to run Docker without root
- How to search for a Docker image
- How to install a Docker image
- How to run a Docker image
- How to monitor Docker with various commands
Docker running a container image on AlmaLinux
Mediawiki easy deployment with Docker container
About
The automated build docker Mediawiki system (CMS) image “linuxconfig/mediawiki” can be used to instantly deploy Mediawiki on your docker hosts.
Configuration
The Mediawiki runs on Debian GNU/Linux system featuring Apache web server, MariaDB ( MySQL ), database and PHP5. A new docker container based on “linuxconfig/mediawiki” will expose port 80 which can be linked to the docker host port for an immediate Mediawiki web configuration/installation access.
How to remove all docker images stored in a local repository
The following linux commands can be used to remove all Docker images stored in your local repository. Be aware that you would not be able to undo any of the removed docker images. First, list all your docker images to make sure that there is nothing you want to remove:
# docker images
Using the following linux command you can obtain image IDs of all your docker images:
# docker images -q
To remove a single docker image simply run docker rmi followed by the image ID. For example:
# docker rmi 9fa0e1f381ad