Here we have compiled the most probable DevOps interview questions asked in the industry. You will learn about software version control, Git repository, reverting a commit in Git, Vagrant, continuous testing elements, and the importance of continuous integration, testing, and deployment. These questions are curated after discussing with many interviewers and DevOps Training experts.
Yes, you can edit and update a container. Go to your container, update it with whatever you want and then, execute the following command in the docker environment but not in a container.
$ docker commit < container-id > < username/image-name >
$ docker push < username/image-name > (this will take tag "latest" as default) to tag your own versions you should mention tags as
$ docker push
Use the following command to delete a stopped container:
$ docker rm < container-id >
Use the following command to delete a running container:
$ docker rm -f < container-id >
-f flag stands for force.
No, you don’t lose any data when you exit Docker container. Data that you save in the container gets preserved on the disk until you explicitly delete the data or container.
To delete an image form the local Docker machine is as follows:
$ docker rmi image_id
$ docker system prune
This command is used to remove all the stopped containers, all the networks that are not used, all dangling images and all build caches. It’s one of the most useful docker commands.
A command line interface (CLI) is known as a client of docker (the docker command). Docker has CLI to interact with Docker daemon.
Any type of applications can be made running on the same hardware using docker containers, it is easy for engineers to create containerized applications and it makes managing and deploying much more easier. Even it is very easy to deploy docker containers in any cloud based environment. You can even share containers with your applications.
You can use JSON instead of YAML for your compose file, to use JSON file with compose, specify the JSON filename to use, for eg:
$ docker-compose -f docker-compose.json up.