Here's a solution when the docker container exits normally and you can edit the Dockerfile.
Generally, when a docker container is run, an application is served by running a command. From the Dockerfile reference,
Both CMD and ENTRYPOINT instructions define what command gets executed when
running a container. ...
Dockerfile should specify at least one of CMD or ENTRYPOINT commands.
When you build a image and not specify any command with CMD or ENTRYPOINT, the base image's CMD or ENTRYPOINT command would be executed.
For example, the Official Ubuntu Dockerfile has CMD ["/bin/bash"]
(https://hub.docker.com/_/ubuntu). Now, the bin/bash/
command can accept input and docker run -it IMAGE_ID
command attaches STDIN to the container. The result is that you get an interactive terminal and the container keeps running.
When a command with CMD or ENTRYPOINT is specified in the Dockerfile, this command gets executed when running the container. Now, if this command can finish without requiring any input, it will finish and the container will exit. docker run -it IMAGE_ID
will NOT provide the interactive terminal in this case. An example would be the docker image built from the Dockerfile below-
FROM ubuntu
ENTRYPOINT echo hello
If you need to go to the terminal of this image, you will need to keep the container running by modifying the entrypoint command.
FROM ubuntu
ENTRYPOINT echo hello && sleep infinity
After running the container normally with docker run IMAGE_ID
, you can just go to another terminal and use docker exec -it CONTAINER_ID bash
to get the container's terminal.