“ docker run”命令中“ sandbox”是什么意思？

Question

I am running the Docker image with Apache Spark :

docker run -i -t -h sandbox sequenceiq/spark:1.2.1-ubuntu /etc/bootstrap.sh -bash

I can know the meaning of " -i ", " -t " and " -h " after executing " docker run --help " command. But how can I explain the " sandbox " here? Is it a option of " docker run " command? I can't find it in the output of " docker run --help ".

Answer 1

In that command, sandbox is the argument for -h option. So sandbox will be the hostname of the container you are creating. It has not any special meaning and could be any hostname you wish.

Answer 2

The process launched by docker run has no access to the other processes on your host, this is more or less a sandbox. When you launch a docker container (say a webserver such as nginx), and you go inside with a docker exec you can do a ps -ef and you only see the processes of nginx and your docker exec not all the processes of your host