Question:- Define Containerization.
Answer:- Containerization is a form of virtualization through which applications are run in containers (isolated user spaces) all using a shared OS. It packs or encapsulates software code and all its dependencies for it to run in a consistent and uniform manner on any infrastructure.
Question:- What is the benefit of using a Docker over a Hypervisor?
Answer:- Though Docker and Hypervisor might do the same job overall, there are many differences between them in terms of how they work. Docker can be thought of as lightweight since it uses very few resources and also the host kernel rather than creating it like a Hypervisor.
Question:- What are the unique features of Docker over other containerization technologies?
Answer:- Some of the most important and unique features of Docker are as follows: • We can run our Docker container either on our PC or on our enterprise IT system. • Along with the Docker Hub, which is a repository of all containers, we can deploy and download all our applications from a central location. • We can even share our applications with the containers that we create.
Question:- What is a Docker image?
Answer:- A Docker image helps in creating Docker containers. We can create the Docker image with the build command; due to this, it creates a container that starts when it begins to run. All the Docker images are stored in the Docker registry such as the public Docker registry. These have minimal amounts of layers within the image so that there is a minimum amount of data on the network.
Question:- What is a Docker container?
Answer:- It is a comprehensive set of applications including all its dependencies which share the same OS kernel, along with the other containers running in separate processes within the operating system in a user space. Docker is not tied to any IT infrastructure, and thus it can run on any computer system or on the cloud. We can create a Docker container using Docker images and then run it, or we can use the images that are already created in the Docker Hub. To simplify things, let’s say that the Docker containers are just runtime instances of the Docker image.
Question:- What is a Docker Hub?
Answer:- We can think of Docker Hub as a cloud registry that lets us link the code repositories, create the images, and test them. We can also store our pushed images, or we can link to the Docker Cloud, so that the images can be deployed to the host. We have a centralized container image discovery resource that can be used for the collaboration of our teams, automating the workflow and distribution, and changing management by creating the development pipeline.
Question:- What is a Docker Swarm?
Answer:- We can think of a Docker Swarm as the way of orchestrating the Docker containers. We will be able to implement Dockers in a cluster. We can convert our Docker pools into a single Docker Swarm for easy management and monitoring.
Question:- What is the use of a Dockerfile?
Answer:- A Dockerfile is a set of specific instructions that we need to pass on to Docker so that the images can be built. We can think of the Dockerfile as a text document which has all the commands that are needed for creating a Docker image. We can create an automated build that lets us execute multiple command lines one after the other.
Question:- What is Docker Compose?
Answer:- Docker Compose defines and runs multi-container Docker applications. With Compose, a YAML file is used to configure an application’s services. All the services from the configuration can be created and started with a single command.
Question:- Why use Docker?
Answer:- Following are the reasons why one should use Docker: It allows the use of system resources more efficiently Software delivery cycles are faster with it Application portability is possible and easy It is great for the microservices architecture
Question:- What are the drawbacks of Docker?
Answer:- Docker has a few drawbacks as listed below: • No storage option • Poor monitoring • Unable to automatically reschedule inactive nodes • Has a complicated automatic horizontal scaling setup
Question:- What is Docker Engine?
Answer:- Docker Engine is an open-source containerization technology that facilitates the development, assembling, shipping, and running of applications with the help of the following components: • Docker Daemon • Docker Engine REST API • Docker CLI
Question:- What are registries?
Answer:- Docker registries provide locations for storing and downloading images. There are two types of registries • Public registry • Private registry Public registries include Docker Hub and Docker Cloud.
Question:- What are Docker namespaces?
Answer:- When a container is run, Docker creates a set of isolated workspaces for the container called namespaces.