It uses tmpnb (http://lambdaops.com/ipythonjupyter-tmpnb-debuts) to spin up docker instances of a relatively basic IPython demo. I guess they are a bit overloaded right now. Pretty nice gateway drug to show the benefits of IPython to non-technical folks.

It's not mentionned in the article so I don't see how they handled security? Espcially network wise, how do they prevent spamming?

I imported smtplib and was able to connect to my SMTP server. I didn't try to send any mail though.

Apparently they're running on machines with 24 Xeon cores too

print(open('/proc/cpuinfo').read())

Seems to have network access... I git cloned a small repo from git hub. It already has gcc installed. Looks like they should lock it down a bit more.

It's a tech demo; it'll be more locked down (no network access). The main thing is to tweak the host so the docker containers are routable to the proxy but no external network.

The 24 core Xeons are our (rackspace) OnMetal high memory boxes, you don't actually have 24 cores, docker just pulled that from the host, each container is limited.

I assume everyone gets their own notebook (hence the Docker container), and so you'd only be spamming you.

that's correct

I see. Thank you.

Yeah, we'll do our best to scale this out a bit more. We prepped for 512 concurrent users, got plenty more.

Try again now, it should be back up. We just started a bigger server to let more people on at once.