How do I get into a Docker container?

Question

I'm getting started working with Docker. I'm using the WordPress base image and docker-compose.

I'm trying to ssh into one of the containers to inspect the files/directories that were created during the initial build. I tried to run docker-compose run containername ls -la, but that didn't do anything. Even if it did, I'd rather have a console where I can traverse the directory structure, rather than run a single command. What is the right way to do this with Docker?

Answer 1

Use:

docker attach <container name/id here>

The other way, albeit there is a danger to it, is to use attach, but if you Ctrl + C to exit the session, you will also stop the container. If you just want to see what is happening, use docker logs -f.

:~$ docker attach --help
Usage:  docker attach [OPTIONS] CONTAINER

Attach to a running container

Options:
      --detach-keys string   Override the key sequence for detaching a container
      --help                 Print usage
      --no-stdin             Do not attach STDIN
      --sig-proxy            Proxy all received signals to the process (default true)

Answer 2

Use this command:

docker exec -it containerid /bin/bash

Answer 3

To connect to cmd in a Windows container, use

docker exec -it d8c25fde2769 cmd

Where d8c25fde2769 is the container id.

Answer 4

For docker-compose up (Docker4Drupal)

docker-compose exec php bash

I use Docker for Drupal on a Linux laptop. After running the container I use 'docker-compose exec php bash' to connect with the container so I can run drush commandos. It works fine for me.

Answer 5

If you are using Docker Compose then this will take you inside a Docker container.

docker-compose run container_name /bin/bash

Inside the container it will take you to WORKDIR defined in the Dockerfile. You can change your work directory by

WORKDIR directory_path # E.g  /usr/src -> container's path

Answer 6

It is simple!

List out all your Docker images:

sudo docker images

On my system it showed the following output:

REPOSITORY          TAG                 IMAGE ID            CREATED             VIRTUAL SIZE
bash                latest              922b9cc3ea5e        9 hours ago
14.03 MB
ubuntu              latest              7feff7652c69        5 weeks ago         81.15 MB

I have two Docker images on my PC. Let's say I want to run the first one.

sudo docker run -i -t ubuntu:latest /bin/bash

This will give you terminal control of the container. Now you can do all type of shell operations inside the container. Like doing ls will output all folders in the root of the file system.

bin  boot  dev  etc  home  lib  lib64  media  mnt  opt  proc  root  run  sbin  srv  sys  tmp  usr  var