support ssh access to containers about violet

[sbshrey]

SSH into a Container
How do I SSH into a running container
There is a docker exec command that can be used to connect to a container that is already running.

Use docker ps to get the name of the existing container
Use the command docker exec -it /bin/bash to get a bash shell in the container
Generically, use docker exec -it to execute whatever command you specify in the container.

reference: http://phase2.github.io/devtools/common-tasks/ssh-into-a-container/