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Raspberry Pi Virtual PC

System splatpi is a single board computer on the SplatSpace local area network that presents a GUI desktop to client computers one user at a time.

(HINT: If you edit this section you get access to all the sections below too. Saves a lot of mouse clicks!!)


  • IP
  • Hardware:
    • Rev 1 Model B Raspberry Pi (1/4gb (rev 1)
    • Seagate 160gb 3 1/2inch disk drive.
    • Coming: buffered async serial and I2C buses
  • Software:
    • 12/16/12 Raspbian (aka Debian 7 aka wheezy) with patches current as of 1/31/13.


This system is intended to be freely available with no restrictions on use except:

  • Do not disturb the hardware except to do an emergency restart (see below), leave the /boot and /R{2,3,4} filesystems untouched, and leave ipv6 off for now. Also don't dream of disabling syslog, removing logs, or modifying sudo logging.
  • Be careful with superuser commands. If you aren't comfortable modifying the system, ask for help.


  • Intended GUI access (renders a 1024x768 desktop):
    • Command: vncviewer
    • On Windows you'll of course use a GUI [[1]]. This is NOT the same thing as remote desktop connection.
    • Only one vnc session is available at a time. The 2nd through Nth person using a VNC viewer will unfortunately get little or no feedback, depending on what viewer they are using. We'll hopefully provide some means of determining the state of the system in the future.
    • REMEMBER to stop your viewer session when you're done so others can use the GUI interface. But if you just turn off/disconnect your laptop, that
  • Example text interface login (password "raspberry"):
    • Command: ssh -l pi
    • concurrent ssh logins are supported, but watch out about overloading the system. The "uptime" command let's you know how many users are on the system and the load average (most recent, through oldest/smoothed load average). Note that the user corresponding to VNC access is always "on", even if nobody is using a vncviewer.
  • The system has an echo server so it will respond to ping. An easy status check is with the command below, but if the system is thrashing this can take a very long time to put up a prompt and then complete:
    • ssh -l pi uptime
  • EMERGENCY power cycling instructions
    • First ask yourself: Is the system unresponsive because my vncviewer is crap, I'm trying to pretend Windows remote desktop is the same thing as VNC, I forgot the -l on the ssh command, somebody else is using the system and or previously used it and in any case it's currently thrashing the disk, etc?
    • CAREFULLY do this:
      • Pick up the RPi (blue plastic case sitting near the "trihack" server on the table near the rack cabinet) so you can push on the (broken) ethernet connector to jam the RPi into the end of the case where the SD card sticks out. The key here is to keep the RPi snug against this end of the box so the power connector goes in properly.
      • Pull the power connector out, then put it back in, double checking that the RPi is flush against that end of the case.
      • Peek near the end of the case having the ethernet connector and confirm the red LED is shining.
      • Put the box back down gently

General Project Idea List

  • Howtos, demos
  • Graphics files for 1024x768 desktop backgrounds
  • Scratch, Python, other program examples
  • Games
  • A brother or sister for splatpi dedicated to _____?
  • A daughterboard (and alternative case) that enables possibilities such as I2C and/or SPI buses for brother/sister systems (whether they are RPis, Arduinos, etc).
  • And Arduino or other system that talks to splatpi (e.g. via the UART) and mediates connections to other systems. That is, something that buffers splatpi from misbehaving bus peripherals.
  • Sensors fed via the hardware to monitor the room's temperature, light level, sound level, etc, and feed that via CGI or the like to the splatspace.org web server while keeping the overhead LOW.

Admin Todo List

For designated admins and folks experienced with Linux and in tune with the vibes. The one rule: EDIT THIS PAGE to clue folks into changes.

  • Properly configure router cabling so another connection isn't "stolen." Note that the current CAT 5 cable has broken (tab missing) connectors on both ends and needs replacing which is why the cable wasn't fed from the back of the rack cabinet to start with!
  • The system should probably live on a shelf on the back wall so there's room for it to get friendly with like-minded single board computers that want to share warm copper.
  • Fix the clearance of the power connector in the case so the board sliding around inside the case doesn't cause the plug to come loose.
  • Arrange a one or more switches for conveniently forcing system restarts and put them in a box underneath a checklist that discourages rash acts stemming from ignorance.
  • Add a comment to /etc/modules saying do NOT add "ipv6" and then think hard about the implications of enabling IPV6 if that by definition enables access from arbitrary clients on the Internet. Maybe consider a "hardenedpi" system that is fully accessible but not begging instant corruption by hackers who get the address.
  • Add "noauto" option and pull "user" option if present for /boot in /etc/fstab to make it harder to get munged.
  • The hard drive's partition table should be edited so one of the other partitions is identical in size to the one for root and a backup copy should be made. There should likewise be a second SD card rubber banded to the bottom of the RPi's case so when the one root gets ruined the SD card is swapped and the boot process is steered to the backup. The backup could be periodically sync'd with the current root *after confirming it's healthy*. Any SD card 64mb or larger would work for this.
  • Set up bonjour or equivalent so the system can be accessed with a name IP address
  • Feed system status to the splatspace.org web server via CGI or the like. Keep the overhead low!
  • Nicer and maybe randomly variable desktop background graphics

Page creation: Petesoper 10:19, 1 February 2013 (MST)