How to run two nodes in one docker container?

Question

Node.js

I have a script that launches docker with a node

echo "* Run the new container *"
ssh -i "test-docker.pem" [email protected] 'docker run -d --name docker-backend -e="NODE_ENV=development" -p 3000:3000 esign/docker-backend:current'

I am zero in docker, and I need to start another instance with another mail, how can I do this?