在后台Docker容器中运行apache / php / nginx

Question

I am new to docker. I am trying to run a docker container running Apache and PHP or PHP-FPM.

Like that

docker run -p 80:80 --name my-apache-php-app -v "$PWD":/var/www/html php:7.0-apache

And it attaches STDIN/STDOUT to my host machine

docker run -d -p 80:80 --name my-apache-php-app -v "$PWD":/var/www/html php:7.0-apache

Seems to work fine, but I read that

By design, containers started in detached mode exit when the root process used to run the container exits.

Does it mean if I start container from remote ssh connection and then close it, the docker container will stop ?

I am building my custom docker image based on the

library/php/

And I need my image to start automatically in background, not in foreground.

How can I get this behavior ?

Answer 1

By design, containers started in detached mode exit when the root process used to run the container exits.

The root process in this context is the root process inside the container, not the root process used to docker run the container. This process is typically an ENTRYPOINT or CMD in the Dockerfile. For Nginx, often you see something like:

ENTRYPOINT ['nginx', '-g', 'daemon off']

This container would exit when the nginx process exits (which shouldn't be immediately unless your nginx configuration is bad, or some other error kills it).

If you were to have an ENTRYPOINT like this:

ENTRYPOINT ['nginx', '-t']

Then the container would test any nginx confs it found, give you the result in STDOUT, and exit.