bringing old Pi boxes back online

While I was in Wally World my devices were updating over their wifi (repeated in the van). Two of the devices were a Pi and Pi2 I brought back online. The Pi 3 does the DVR duties and the others have just been sitting in a plastic pencil box.  They are small enough I brought them with me with no particular idea how they’d be used. 

These two are “headless”, which is to say installed and run without monitor, kb, mouse, etc.  Just the little devices themselves.   The main proglem with that is SSH is turned off by default, making connecting to them problematic.  Luckily, touching a file called ssh in the boot dir enables ssh so you can get in and finish setup.  Theoretically you can set up wifi similarly, but I stole the cat5 out of the old-school HDHR tuner to get into them and set up the wireless.

I wanted to get the Pi boxen running again so I’d have a low-power linux option in the van.  The Dell workhorse slurps power like crazy (up to 90w when all cores are glowing) and the linux virtual on the chromebook was castrated to the point of meaninglessness.   The Pi3 has its hands full with DVR duties, particularly when processing or playing HD.  So having a couple low-power dedicated boxes to play with might be nice.  And maybe if I get some tax money back this year I’ll grab a used P4 for the OTA. 

Since they are headless I installed Raspberry Pi OS Lite (based on Debian Buster) instead of the full version.  No X, no fancy stuff.  Since there were no graphics I turned the RAM allotted to video to 64MB –> 16MB, the lowest amount shown.  Maybe It can go lower without crashing,.  I dunno.

Possible uses for the Pi boxes:

• head for a Gridseed scrypt miner 2x 40-chip boards.  I used to have a antminer bitcoin rig but it took about 1000w which I can’t make in the van.  I gave it to a cow-orker when I moved into the van.  Scrypt is memory-intensive rather than power-intensive, to the rig runs on about 80w.  Not bad, but if the Dell is running as the head…  I got the mining software compiled on the Pi2 without too much drama but haven’t put it to use. 

• wardriving (warcamping?) an Alfa wifi dongle.   The Pi pulls about 5w while running the Alfa, so it could be run 24/7 on very little power.   airodump-ng is running on the pi2 right now…  Any actual psk would have to be processed on the dell since the Pi lack the grunt for heavy hashing loads.

• Calibre library (currently using the dell)

• ???