Computing stuff tied to the physical world

Back-soon server

In Hardware, Software on Jan 31, 2011 at 00:01

Soon, I’m going to move the JeeLabs server to a new spot in the house. Out of sight, now that the setup is stable.

But to do so requires rerouting an ethernet cable to the internet modem downstairs.

To do it right, I’d like to have a “we will be back soon” surrogate server plugged into the internet modem while transitioning, so that the status is reported on-line:

Screen Shot 2011 01 30 at 16.36.21

I could plug in a temporary Linux box, of course, or a laptop. But I want to keep this option available at all times, so a dedicated solution would be more practical. That way I can easily take the server off-line at any moment.

Ah, but that’s easy, with an Ether Card and an RBBB:

Dsc 2434

This combination just needs a 5..6V power supply, and 6 wires between the RBBB and the Ether Card.

Here’s the backSoon.pde sketch, which I’ve added to the EtherCard library:

Screen Shot 2011 01 30 at 17.24.05

In this case, being able to configure the MAC address of the interface as well as the IP address is in fact quite convenient, because this way the modem needn’t notice the hardware switch.

Only needs about 6 Kb. Actually, I’ll probably add a wireless option and use a JeeNode instead, to report total hits every once in a while. But either way, such a “back-soon server” really doesn’t come any simpler than that!

So if one of these days you see that message while surfing at JeeLabs, you know where it’s coming from :)

PS. I’ve put the back-soon server on-line as a test, it can be reached at

  1. i was wondering what is the use for this in code repository ;)) have you done any testing as how many requests/minute can this puppy get ?

  2. Looks like a good secure solution too. All too often a standby machine isn’t configured too well, out of date kernel/Apache etc which could be exploited.

    Not much to exploit on your matchbox sized server! Even if you did all you could probably do is crash it… Maybe you should stick a watchdog reset on it too, just in case ;-)

    BTW, did you find why your “big” server’s web log virtual machine decided to go bye bye the other day?

  3. You could get really cute and include a small image in hex to the sketch, then add it to your HTML. Check the request for the “GET /logo.gif” and then send the image back instead of the page :-)

    Or you could take the easy route and just include an img src link to a website that will be up…

    I hope the blog comments don’t interpret HTML literally or the above will appear as an image and not the HTML I intended… Oh well, only one way to find out… SUBMIT!


    • Oh, that answer that then! It removed the HTML completely!

      Okay, attempt #2

      <img src=”″>

Comments are closed.