When you create a Dockerfile, you can use two different commands to build your context. Building a context means including the files and directories that you want from your local machine, to be in your container when it’s created. These files may be directories in your local machine, a URL from which you want to download files, or a compressed tarball file that you want to include as it is or after extracting the tarball file.We can use two different instructions to add the files from the build context in the local machine to the Docker container. These are the ... Read More

We can build Docker images by specifying instructions inside a Dockerfile. Dockerfile allows us to specify step-by-step instructions which define the rules for making a container environment. The Docker containers are created for specific tasks and processes to be run inside them. There are three important instructions that are used inside a Dockerfile which lets us define which processes need to be run inside the containers and in what sequence and order.These 3 instructions are -RUNCMDENTRYPOINTThe RUN instruction is quite simple. We can define simple subcommands along with the RUN instruction that we want to execute inside the container. For ... Read More

Vagrant is a software that allows you to create a virtual machine that replicates the user's experience exactly as they want to set it up. Specifically, Vagrant allows you to test your application in a specific environment by mirroring the OS and all appropriate configurations.Whereas Docker is a framework that lets you containerize your app and build so-called microenvironments for deploying it without having to run a whole VM. Each container is a separate isolated environment that contains a unique application environment.As a result, programmers, testers, and DevOps engineers are able to spend less time debugging and identifying important bugs ... Read More

Docker allows you to create containerized, packaged, and isolated environments called Docker containers using Docker images. Inside these Docker containers, you can build, test, and even deploy your applications. This allows you to easily share your application run-time environment with other developers. All of this is possible because of a read-only template called Docker images.You can pull Docker images directly from any Docker registry such as Dockerhub or use a bse image inside a Dockerfile to build your own custom images. You can then use the Docker build command to build your Docker images. Once you have your Docker image ... Read More

Docker allows you to remove old and stale containers that are of no use to you. You can use the Docker rm or Docker container rm commands to do so. However, before you start removing your containers, you need to make sure that none of your containers are actively running. In such a case, Docker will throw an error.However, there is another workaround to this. You can remove Docker containers forcefully using the --force option as well. The Docker remove commands allow you to remove one or more Docker containers together. You just need to specify the container IDs or ... Read More

Docker provides a plethora of useful Docker commands that will help you to create, manipulate, and manage Docker objects such as volumes, images, containers, networks, etc. If you have been working with Docker for a long time now, you might have several Docker images already in your machine. Keeping track of all these images becomes quite difficult especially through a single command line.However, you can list all Docker images along with filtered outputs to get your desired results. In this article, we will discuss how to use different commands along with multiple options to list all Docker images in our ... Read More

Managing multiple Docker containers in a single host machine through a single command line can become tough. Hence, it’s better to know the Docker commands to manage containers the best possible way. Docker provides us with many command line tools and utilities to manage containers. In this article, we will discuss how to list Docker containers through multiple ways. We will also look at how to filter the list output to get the desired results. So without any further ado, let’s get started.Listing Docker ContainersPredominantly, there are two major commands that you can use to display a list of all ... Read More

If you are working with Docker for a long time now, you might already have lots of containers running in your host machine. At times, it becomes really difficult to keep track of all these containers. Moreover, if you are on a network or using compose, there might be several containers running inside the network. In such a case, determining which container is actively running and which has failed, is very difficult. You might need to ping these containers periodically to check their status. For this, you need to have the IP addresses of the containers.You can easily get the ... Read More

When you execute the Docker pull command or Docker run command, the daemon first checks for a similar image in the local machine by comparing the digests of the image.If it finds a match, then it’s not required to search the registry for the image and the daemon can simply create a copy of the already existing image. However, if a copy is not found, it starts pulling it from the registry. The same is the case when you try to build images using a Dockerfile.We all know that Docker images are multi-layered files containing multiple image layers on top ... Read More

While creating Docker images, you specify the build context for the image. The Image build context contains all the files that you want to be included inside the container that you will be from that image. This includes the source code of your application, Dockerfile, other system files, etc. Once you have specified the location of the build context using the Docker build command, you can build the image.Moreover, you can use the COPY instruction inside a Dockerfile or even the Docker cp command to copy files inside the container from the local machine. But what if you want to ... Read More