Ramalakshmi – Best DevOps

7. List of 20 docker commands and its use cases with example? by Ramalakshmi

Ramalakshmi — Mon, 29 Aug 2022 13:45:02 +0000

docker pull: pull the image from the docker hub
docker ps: list the running containers
docker ps -a: list the running and stopped containers
docker start start the container
docker stop: stop the one or more running containers
docker restart: restart the container
docker rm: remove the container
docker exec: runs a new command in a running container
docker image: show all image
docker info: show the information about docker installation
docker kill: kill one or more running containers
docker login: login into docker register

6. What is the differenet between CMD vs Entrypoint? by Ramalakshmi

Ramalakshmi — Mon, 29 Aug 2022 13:26:11 +0000

CMD: Default parameters can be override from the Command Line Interface when container is running
ENTRYPOINT: Default parameters cannot be override from the Command Line Interface when Container running

5. List of dockerfile instructions and its Brief Summary? by Ramalakshmi

Ramalakshmi — Mon, 29 Aug 2022 13:16:24 +0000

FROM: specify the valid docker image name, LABEL: metadata infomation to the image, ADD: copy files, directories and remote URL files to the destination, RUN: executes any command, WORKDIR: set the working directory, ENV: set environment variables with key and value, COPY: copy files, directories and remote URL files to the destination, MAINTAINER: author who create the docker image

1. Components of Docker and its Brief Summary? by Ramalakshmi

Ramalakshmi — Mon, 29 Aug 2022 13:01:12 +0000

Docker follows Client-Server architecture. Docker having three main components Docker Client, Docker Host, and Docker Registry.
Docker Client: Docker client uses REST APIs to communicate with the Docker server when the client send commands to the server, server receives commands in the form of REST APIs request.
Docker Host: Docker Host is used to provide an environment to execute and run applications. It contains the docker daemon, images, containers, networks, and storage.
Docker Registry: Docker Registry manages and stores the docker images

4. What is the differenet between docker exec and attach? by Ramalakshmi

Ramalakshmi — Mon, 29 Aug 2022 12:45:08 +0000

docker exec executes a new command or create a new process in the container. while docker attach just connects the standard input or output or error to a running container using the container ID or name

3. What is the differenet between docker stop and kill? by Ramalakshmi

Ramalakshmi — Mon, 29 Aug 2022 12:22:19 +0000

Stop: The docker stop command stop one or more running containers, By sending “SIGTERM” signal inside the container and stop the process
Kill: The docker kill command kill one or more running containers, By sending “SIGKILL” signal inside the container and kill the process immediately

2. What is the differenet between docker pause and unpause? by Ramalakshmi

Ramalakshmi — Mon, 29 Aug 2022 12:19:09 +0000

Pause: The docker pause command suspends all processes in the specified containers. when suspending a process the SIGSTOP signal is used, which is observable by the process being suspended
Unpause: The docker unpause command unsuspends all processes in the specified containers.