How do I get into a Docker container's shell?

To access a Docker container’s shell, use the docker exec command with the -it flags (interactive terminal). Here’s how:

1. Access Shell in a Running Container

docker exec -it <container_name_or_id> /bin/sh
# or (if Bash is available)
docker exec -it <container_name_or_id> /bin/bash

Example:

docker exec -it my_nginx_container /bin/bash

2. Find the Container Name/ID

List running containers to identify your target:

docker ps
# Output:
# CONTAINER ID   IMAGE          COMMAND                  CREATED       STATUS       PORTS     NAMES
# a1b2c3d4e5f6   nginx:latest   "/docker-entrypoint.…"   2 hours ago   Up 2 hours   80/tcp    my_nginx_container

3. If the Container Isn’t Running

Start the container first (if stopped):

docker start <container_name_or_id>

4. Start a New Container with Shell Access

If you need to start a new container and immediately access its shell:

docker run -it --name my_temp_container <image_name> /bin/sh
# Example:
docker run -it --rm alpine /bin/sh  # Uses Alpine's `sh` shell

5. Common Shell Paths

Alpine-based images: /bin/sh (uses ash shell)
Debian/Ubuntu-based images: /bin/bash
If unsure: Check the image documentation or use ls /bin/*sh.

Troubleshooting

“No such file or directory”: The shell (e.g., /bin/bash) isn’t installed in the container. Use /bin/sh or modify the image to include a shell.
Override the entrypoint (if the default blocks shell access):

  docker exec -it --entrypoint /bin/sh <container_name>

Key Notes

Use Ctrl+D or type exit to leave the shell.
The --rm flag in docker run automatically removes the container when you exit.
For minimal images (e.g., scratch), a shell may not exist—modify the Dockerfile to include one.

How do I get into a Docker container’s shell?