When it comes to cracking an interview, you will need to put a lot of efforts and use your knowledge to crack it. Cracking an interview will definitely help you in giving a structure to your career as you will be sitting in an office, knowing about your career development procedures, and earn a good amount of money per month to support your family and yourselves. You need not have to depend on anyone, and we do understand that. Therefore, our experts and professionals have come up with docker interview questions and answers that will assist you in preparing for the interview and crack it.
Docker is basically a set of multiple SaaS (Software as a Service) and PaaS (Platform as a Service) products that utilize the OS-level system of virtualization to build and deliver software in many packages, known as containers. The software that is hosting the containers is known as Docker engines. It was initially introduced in the year of 2013 and is created by the Docker Inc. company. It offers both the services, free as well as premium where you have the option to choose the best one depending on your demands and requirements.
Docker is an open-source lightweight containerization technology. It has gained widespread popularity in the cloud and application packaging world. It allows you to automate the deployment of applications in lightweight and portable containers.
Here, are a major advantage of using Docker.
Here are the essential features of Docker:
Some notable drawbacks of Docker are:
The Docker image help to create Docker containers. You can create the Docker image with the build command. Due to this, it creates a container that starts when it begins to run. Every docker images are stored in the Docker registry.
Docker daemon or Docker engine represents the server. The docker daemon and the clients should be run on the same or remote host, which can communicate through command-line client binary and full RESTful API.
Dockers public registry is called Docker hub, which allows you to store images privately. In Docker hub, you can store millions of images.
$ docker ps
$ sudo docker stop container name
$ sudo docker run -i -t alpine /bin/bash
The common instruction in Dockerfile are: FROM, LABEL, RUN, and CMD.
Memory-swap is a modified flag that only has meaning if- memory is also set. Swap allows the container to write express memory requirements to disk when the container has exhausted all the RAM which is available to it.
Docker Swarm is native gathering for docker which helps you to a group of Docker hosts into a single and virtual docker host. It offers the standard docker application program interface.
Docker states and Docker Events are used to monitoring docker in the production environment.
Important states of Docker container are:
Docker hub is a cloud-based registry that which helps you to link to code repositories. It allows you to build, test, store your image in Docker cloud. You can also deploy the image to your host with the help of Docker hub.
Docker object labels is a method for applying metadata to docker objects including, images, containers, volumes, network, swam nodes, and services.
FROM pyhton:2.7-slim WORKDIR /app COPY . /app docker build –tag
You need to navigate:
/var/lib/docker/volumes
You can communicate between Docker client and Docker Daemon with the combination of Rest API, socket.IO, and TCP.
You need to do the following things:
In docker file, we need to use COPY or ADD directive. This is useful to relocate code. However, we should use a volume if we want to make changes.
The Docker containers can be scaled to any level starting from a few hundred to even thousands or millions of containers. The only condition for this is that the containers need the memory and the OS at all times, and there should not be a constraint when the Docker is getting scaled.
Below are the steps for Docker life cycle:
CNM stands for Container Networking Model. It is a standard or specification from Docker, Inc. that forms the basis of container networking in a Docker environment. This dockers approach provides container networking with support for multiple network drivers.
Yes, Docker provides support IPv6. IPv6 networking is supported only on Docker daemons runs on Linux hosts. However, if you want to enable IPv6 support in the Docker daemon, you need to modify /etc/docker/daemon.json and set the ipv6 key to true.
No, any data that your application writes to disk get stored in container. The file system for the contain persists even after the container halts.
Bind mounts- It can be stored anywhere on the host system
To configure the Docker daemon to default to a specific logging driver. You need to set the value of log-driver to the name of the logging drive the daemon.jason.fie.
There are many companies who are looking to hire individuals who have the expertise and knowledge about docker engine programming systems. As most of the application hosts require Docker Engine setups, it’s quite important to know that these hirers look forward to those individuals who are not only well-versed with the application but also know how to handle the pressure. Therefore, if you think that you have the right expertise and skill to become a docker engine programmer, then it’s the right time for you to start giving interviews in the companies. As a fresher, you have the scope to earn about 138,017 dollars per annum, and if you are experienced, then you can earn up to 230,000 dollars per annum
When it comes to giving interviews and cracking it with flying colors, then you can use our Docker interview questions and answers that are prepared by our experts and professionals. You can also drop us a message to clarify your doubts or queries.