RaspberryPi VAX cluster: I haven’t forgotten about you!

Hi, sorry for the lack of articles and updates. I haven’t abandoned the project, actually I’ve been too busy building up the hardware together and working and figuring out silly things like the TCP/IP routing (yes, I did end up doing that and now I know how to build a TCP/IP gateway in NetBSD!), power wiring (with help from dad’s soldering skills) and the actual software setups.

So far I now have the Atom motherboard plus a second GBit NIC installed and working. It boots NetBSD 5.1.2 from a 32GB SSD and routes traffic from the internal 10.0.0.x network to any external network I configure on the external LAN port, meaning any internal node has internet access. I even added DNS forwarding on the Intel board so the unit only requires configuring at the external ethernet port (Intel/NetBSD system) and nowhere else. There is also a bridge in place to bridge packets between the interfaces on the Intel board this is purely so the DECnet nodes can see my main LAN and my Area Router.

The aforementioned soldering skills yielded a 4-pin MOLEX adapter with a 12V out and 5V out wires to run the internal Switch and the internal USB hub. The switch does all the internal networking. The USB hub (which has a power switch on the lid) powers the Raspberry Pis via a couple of Blackberry USB charger cables (because they are only 30cm long!). The upshot of this fancy wiring means the whole unit powers on from the ATX power button on the front panel… which is awesome, no? At present it’s using a PicoITX 120W PSU but because there’s a gaping hole in the back panel, and I think I might be overstretching the PicoITX a little, I am replacing it with a full ATX PSU before I finalise the box.

The Raspberry Pi boards are mounted on trays in the 2 5.25″ drive bays. The USB host and Ethernet ports (and the LEDs) are forward facing, allowng for access fro mthe front of the unit without removing the lid (mostly a diagnostic aid). I will also eventually fit right-angle HDMI adapters to offer a forward facing video port also. The idea is you can pop off the pane that covers the RPi slot and diagnose the board if an issue arises without removing the lid or taking the tray out. I will ultimately slot the 2 faceplates so I can see the LEDs from the outside and refit them (I may also mod them to make them easier to remove).

The whole thing is houses in a 204mm deep 2U rack chassis provided by the excellent folks at xcase.co.uk who have come up with a real gem of a case. It’s perfect for the task and was a very reasonable price (for a rackmount chassis).

You are probably all thinking ‘where are the photos?’. I intend to take some tonight at some stage and post them to Flickr. I will also post them here for your viewing peasure.

So far all this isn’t very retro but that part is coming. All this is groundwork or running the emulators and bootstrapping the OpenVMS 7.3 systems on the individual nodes. I have to learn VMScluster, MOP serving and a few other tricks, which is going to great be fun, I am sure.

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