Translation for those who care:<p>-------------------<p>This time round I got into carpentry for my project. Something that became both expensive and trickier than I had thought when I started. My carpentry knowledge is limited to (high-)school lessons, so take it easy on the results.<p>The project became more expensive than expected. Some 6000 SEK [~$740] including a whole bunch of tools (mill, jig saw, circular saw). Made do with 'Biltema' tools [the IKEA of tools] and returned the first mill after 1 hour of use. The other stopped after around 2 hours so then I fixed that one myself (took apart the start-button and modified it a bit).<p>The project consists of:<p>- 10/100 Mbps switch<p>- Nexus 7<p>- 10A 6 port USB charger<p>- 4 x Raspberry pi 3<p>- 4 x 8GB SD card<p>- TP cables + USB cables<p>- Oak<p>- Plexiglass<p>Anyway, you'd all probably rather see pictures than words.<p>- Nexus 7 with realtime data for all nodes.<p>- 'Economically' bought 8GB, not class 10, but thinking of running a 2.5" HDD for the controller node.<p>- Sleeved all the cables, then realised that they didn't fit with the sleeving. Could only strip them and do again.<p>- First test with 2 x USB hubs that didn't deliver enough current at start-up.<p>- Flip-up "chassis"<p>- My modified netdata page showing real-time data for all nodes, including the temperature.<p>- Running Docker with Kubernetes on the cluster.<p>-------------------<p>[Any errors/omissions are my own]
Looks like it could also act as a radiator :) Especially with the RPi 3 heating issues:<p><a href="https://www.youtube.com/watch?v=e6okZKRwnTQ" rel="nofollow">https://www.youtube.com/watch?v=e6okZKRwnTQ</a>
Check <a href="http://www.pidramble.com/" rel="nofollow">http://www.pidramble.com/</a> for a more compact RasPi cluster. Jeff's uSD benchmarks made it to Hacker News front page previously.
I've long thought about a similar project to test my applications when scaling out and how well concurrency works.<p>One big advantage is that raspberry pies are also so you don't need to send 100MBs to your servers to max out the CPUs (and thus don't need such a quick connection and powerful machine to generate all those requests).
Might the HDD be attached to one Pi this way? It would be interesting if a ghetto SAN could be arrange. Do only the enterprise people get to HDD's with ethernet interfaces directly?<p><a href="http://www.seagate.com/files/www-content/product-content/hdd-fam/kinetic-hdd/en-us/docs/kinetic-ds1835-1-1110us.pdf" rel="nofollow">http://www.seagate.com/files/www-content/product-content/hdd...</a>
RPI's have been shown not to scale from a power/heat to $ ratio (I believe Mac Mini clusters are way more efficient), so this is not a practical project by any means.<p>Even so, very fun looking project. It says something when a geek like me is impressed at an electronics project for the (very nice) woodworking.
Might want to consider sealing the plexiglass in some fashion as the gentle air current under it will collect dust on the side you can't so easily clean.