Suppose that you want to ssh into iver31, but are outside of the lab's
internal 192.168.0.x network (e.g., in your office, off-campus, etc).
Here's how you can easily remotely tunnel into iver31 on the lab's
internal network via your login privileges on robots.

1) on your off-campus machine issue the following
ssh username@robots.engin.umich.edu -L 1234:iver31:22 -L 1235:perlab:22

2) now, from your local machine, ssh directly into iver31 and/or
perlab via the following:
ssh -p 1234 auv@localhost
ssh -p 1235 ryan@localhost

