How to SSH tunnel to a Docker container on a remote server

Docker ssh tunnel

For example temporary connect to Postgres.

1. Expose the port within your Docker container to the remote server

```
# docker.example.com.yaml
version: '3.3'

services:
    postgres:
        image: postgres:9.6-alpine
        ports:
            - "6543:5432"
```

2. Deploy.

3. On your machine, make a tunnel: 

```
ssh -NL 3001:localhost:6543 root@$(docker-machine ip docker.example.com)
```

4. Use psql from your machine.

5. Remove from docker.example.com.yaml "6543:5432" after work cause it's public! And deploy.