What is Docker interview questions and answers?

Top 43 Docker Interview Questions and Answers (2021 Update)

• What is Docker?
• What are the advantages of using Docker container?
• What are the important features of Docker?
• What is Docker image?
• What is Docker Engine?
• Explain Registries.
• What command should you run to see all running container in Docker?

What are the three main types of Docker components?

There are three components in the Docker Engine:

• Server: It is the docker daemon called dockerd. It can create and manage docker images. Containers, networks, etc.
• Rest API: It is used to instruct docker daemon what to do.
• Command Line Interface (CLI): It is a client which is used to enter docker commands.

What are the important Docker commands?

Here’s a List of Docker Commands

• docker run – Runs a command in a new container.
• docker start – Starts one or more stopped containers.
• docker stop – Stops one or more running containers.
• docker build – Builds an image form a Docker file.
• docker pull – Pulls an image or a repository from a registry.

How many Docker containers can I run per host?

Runs Eight Containers per Host. The median company that adopts Docker runs eight containers simultaneously on each host, a figure that has climbed steadily over the years.

How many container we can create in Docker?

Using this simple calculation, we can estimate that we can run about 1,000 containers on a single host with 10GB of available disk space.

What is the lifecycle of Docker container?

Docker Container Lifecycle Management: Create, Run, Pause, Stop And Delete. Docker is a containerization platform for developing, shipping, and running applications inside containers. We can deploy many containers simultaneously on a given host. In this blog, we will talk about Docker Container Lifecycle Management.

What is a image in Docker?

A Docker image is a file used to execute code in a Docker container. Docker images act as a set of instructions to build a Docker container, like a template. An image is comparable to a snapshot in virtual machine (VM) environments. Docker is used to create, run and deploy applications in containers.

What is the format of Docker image?

The OCI format is a specification for container images based on the Docker Image Manifest Version 2, Schema 2 format. Container Registry supports pushing and pulling OCI images.

What are Docker competitors?

Let’s have a look at seven complete packages, which are currently Docker’s most direct competitors.

• Artifactory Docker Registry.
• LXC (Linux)
• Hyper-V and Windows Containers.
• rkt (works with Kubernetes)
• Podman (open-source container engine)
• runC (portability solution)
• containerd (a container runtime)

How much memory is my Docker container using?

If you need more detailed information about a container’s resource usage, use the /containers/(id)/stats API endpoint. On Linux, the Docker CLI reports memory usage by subtracting cache usage from the total memory usage.