Docker Cheatsheet

Advantages

The big advantage of containers is the non existing virtualisation layer. The running application within a docker container actually runs directly on the physical machine as process. If you don’t need to configure the hardware, you better use container instead of VW.

The key thing that Docker provides is the guarantee that the containerized software will always run the same. It doesn’t matter if the code is run locally on Windows, Linux or in the cloud on Azure.

docker usages

Usage: docker run [OPTIONS] IMAGE [COMMAND] [ARG...] Usage: docker exec [OPTIONS] CONTAINER COMMAND [ARG...]

Run an interactive container

Simple

docker run --rm -it <image> bash

-i for interactive -t for allocate a pseudo terminal --rm to remove container when exited bash as command for new process in container

Run a privileged container with mounted volume

docker run -it -v /var/opt/directory:/mounted --privileged --rm rhel7 bash

Override defined entrypoint

This can be used to explore an exited container. docker run -it --entrypoint /bin/bash <image>

Exec into a running container

docker exec -it <container> bash

-i for interactive -t for allocate a pseudo terminal bash as command for new process in container

Show docker stats

docker stats --format "table \t\t\t"

docker stats --format "table \t\t\t\t"

docker ps --format "table \t\t\t"