Docker

This is an exhaustive list of commands used for docker.

To install Docker

To check number of running container | both running and not running

docker ps | docker ps -a

To check number of images on the host

docker images

Run a container using the image | Run a container and specify the name | Run a container with tag and ports

docker run <image> | docker run -d --name <name> <image> | docker run -p <host-port>:<container-port> <image>:<tag> <network-name> <image>

with environment variable | with network (default=bridge other options-none,host)

docker run -e <env-var> <image> | docker run -d -e MYSQL_ROOT_PASSWORD=<password> --name <name> --network 

Example

docker run --network=wp-mysql-network -e DB_Host=mysql-db -e DB_Password=db_pass123 -p 38080:8080 --name webapp --link mysql-db:mysql-db -d kodekloud/simple-webapp-mysql

To open multiple terminals of same docker container

docker exec -it <container_id_or_name> bash

To run container in the background

docker run -d <image>

Stop a container | stop all containers

Ctrl+C / docker stop <container-id> | docker stop $(docker ps -aq)

Delete a container | Delete all containers

docker rm <container-id> | docker rm $(docker ps -aq)

Delete an image | Delete all images {STOP AND DELETE CONTAINERS BEFORE DELETING IMAGES}

docker rmi <image> | docker rmi $(docker images -aq) # Stop and delete containers before deleting images

Pull an iamge

docker pull <image>

Ports

{}:{Port-published-on-the-Host}->{Port-exposed-on-container}/tcp | 0.0.0.0:3456->3456/tcp

To find base image used in Dockerfile

grep -i FROM /<Path>/Dockerfile

To find any parameter in Dockerfile without opening

cat Dockerfile-<image> | grep <parameter>'| cat Dockerfile-mysql | grep ENTRYPOINT | cat Dockerfile-wordpress | grep CMD

To build image from Dockerfile

cd <desired_directory_with_Dockerfile>
docker build -t <image-name>:<tag> .      # "."(dot) indicates for the current directory

To find base OS of the image

docker run <image> cat /etc/*release*

To inspect a container | To check environment variable

docker inspect <container-name> | docker inspect <container-name> | grep -A 10 Env

To know the env field from within a container

docker exec -it <container-name> env

To check number of networks on the system | To inspect bridge

docker network ls |   docker network inspect bridge

docker inspect alpine-1

To create a new network

docker network create --driver bridge --subnet <subnet> --gateway <gateway> <network-name>

To mount a volume to a container (default /var/lib/docker)

docker run -v <data-path>:/var/lib/<data> <image>       |       
docker run \
--mount type=bind,source=<data-path>,target=/var/lib/<data> <image>

Compose a docker (go to the path)

docker-compose up

Rocker

Rocker is a A tool to run docker images with customized local support injected for things like nvidia support and user id specific files for cleaner mounting file permissions.

To install Rocker

Integrated Extensions

There are a number of integrated extensions. Here are some of the highlights. You can get full details on the extensions from the main rocker --help command.

x11 -- Enable the use of X11 inside the container via the host X instance.
nvidia -- Enable NVIDIA graphics cards for rendering
cuda -- Enable NVIDIA CUDA in the container
user -- Create a user inside the container with the same settings as the host and run commands inside the container as that user.
home -- Mount the user's home directory into the container
pulse -- Mount pulse audio into the container
ssh -- Pass through ssh access to the container.
privileged -- Grants a Docker container root capabilities to all devices on the host system

To run Gazebo on Melodic

rocker --nvidia --x11 osrf/ros:melodic-desktop-full gazebo

To mount volumes

--volume /file_path_on_host_pc:/file_path_on_docker. The changes made in the docker will be reflected.

Example:

rocker --nvidia --x11 osrf/ros:humble-desktop-full --volume /home/ros_ws/my_robot_description:/home/ros_ws/my_robot_description

rocker --privileged --x11 --volume ~/Downloads/docker_ros_noetic:/urdf_output --  ros:noetic