March 21, 2019
4 min Read
March 21, 2019
4 min Read
Docker is taking the world by storm because it is a valuable open-source platform that allows applications to run without using an actual virtual machine of any kind. This gives users the flexibility to run and test applications in software containers without the need to worry about compatibility, turning your VPS into a great development platform. In this tutorial, we’ll teach you the basic commands every Docker user should know, including how to remove all imaged on Docker!
When you work with Docker you can be sure that if an app runs on it, it will run smoothly on any other system, screen size, or browser. Docker makes it easy to deploy, launch and then test applications without difficulty. It is quick, saves times and easy to learn!
Let’s learn why Docker is loved by so many users:
Docker does not require complex infrastructure like traditional software applications do. The infrastructure needed is minimal, helping to save the organization a lot of money on virtual machines and related equipment. Docker can be handled with fewer employees, that helps save on spending
Docker works with containers that allow the developer to create, run and test applications on the container itself which ensures smooth operation on any system whatsoever. It allows plenty of room for experimentation that enables developers to make error-free applications which are more portable with easy to set up code bases.
Docker’s features are such that one command takes care of further steps which add to its efficiency and the fast configuration of an application which in return increases productivity.
Docker allows multi-cloud computing as many systems all over the world have embraced it. Amazon Web Services (AWS) and the Google Compute Platform (GCP) are some of the examples where Docker is highly used. Many applications that include OpenStack, Microsoft Azure, Chef, Puppet and more are highly compatible with Docker Containers.
A platform is useless if it has security issues, isn’t it? Docker is secure and fast which means that each application running on Docker Containers stays isolated to each other without causing any kind of security issue. It allows the developer to take charge over full management of the application and the traffic flow without causing server or security issues.
Docker keeps unused files in its garbage collection and uses a cautious method to get rid of the files, images, containers, etc.
In Docker to remove all images, or a few you no longer need, you can use docker system prune.
To remove hovering images that is recent and is not tagged with any command whatsoever:
docker image prune
This will delete all the dangling images. This command cannot be reversed.
To delete images that are present in the existent containers that are tagged:
docker image prune –a
The -a flag makes sure all files are deleted.
To only delete specific images, for example, that may fall under a specific time frame, use the command:
docker image prune -a --filter "until=24h"
When you decide to delete the container it does not automatically remove itself unless you use the –rm (flag). Similarly, in order to see all the unused containers, you will need to run the docker ps –a command.
To remove all the containers that are stopped in the application, follow this command:
docker container prune
To limit the removal of containers that are stopped previously, for example, according to the time frame use the following command:
docker container prune --filter "until=24h"
Volumes are used for multiple containers and it is very likely there will be an collection of unused or stopped volume files.
These files are not removed automatically, neither is there a setting in Docker to do so as that can cause significant loss or damage of data. Use the command:
docker volume prune
There is one way to remove the unused Docker Volumes – if one filters the Docker files and then runs the command automatically.
docker volume prune --filter "label!=keep"
The above command will only delete those Volume files which not labeled and are assigned with keep label.
Though Docker networks don’t take much disk space, it can cause problems further if unnecessary files are not cleared from the disk.
One problem is that it creates iptables rules and bridge networks with routing table entries. The command for removing networks is simple:
docker network prune (cannot be reversed)
docker network prune --filter "until=24h" (For filter based on time frame)
docker system prune
This command will delete everything in the system which includes:
Docker is the only platform to date that allows easy developing options and allows unlimited testing and experimentation to create the most efficient applications. This is the main reason that Docker is gaining considerable momentum today and is on increasing demand.
The Docker Prune Command should be used appropriately or else you might lose data. It necessary for the developer to clear the files once everything is settled, up and running. Otherwise, any loss of data while making the application can cost time and unnecessary stress trying to recover it.