Docker run without ports

General
1

well i’ve been working with docker for a lot of time, but i’ve always worked with containers with ports.
So now i have a concern, how works a container without port i mean. i have Mysql container but it works in 3606 port, but if i work with a container without port and i run it, it doenst run in docker ps.
I need information that how it works or something. Thanks.

I had tried with -it but it is the same, does not run.

And finally i did not get access with docker exec neither.

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2 
# docker container run -e MYSQL_ROOT_PASSWORD=my-secret-pw -d mysql

starts a MySQL container without published ports and it is visible in the container list. Did you forget to set a password? Check the logs if it doesn’t work.

3

Why -e?

But is was not my question.

I mean, if i run

docker run -ti google/cloud-sdk

it works perfectly but if i make a Docker file like

FROM google/cloud-sdk:latest

And then

docker build -t gcloud .

and

docker run -d gcloud

It does not work

4

I gave this answer because you were speaking about MySQL and containers without ports. -e is used to set the environment variable.
I see now that your question is about something else, about the difference between run -it and run -d.
You have to know that a container runs only as long as a foreground process is running inside it. If you start (I use the long syntax and write -it like ‘interactive terminal’ because it’s easier to remember; not important at all)

docker container run -it google/cloud-sdk

then your terminal gets connected to the container and the process running in the foreground is the one you see at the bottom of the Debian Stretch image:

CMD ["bash"]

As soon as you type exit Bash exits too and the container is terminated. If you run

docker container run -d google/cloud-sdk

Bash has nothing to do and exits immediately together with the container. Check this with

docker container ls -a | grep cloud-sdk

This means if you want to run the cloud-sdk as a daemon so you are able to reconnect to it, add something like CMD ["tail", "-f", "/dev/null"] at the bottom of your Dockerfile and connect to the running container with

docker container exec -it name-of-my-container bash