Show HN: Raspberry Pi3 cluster with Docker/Kubernetes | Hacker News Reader

Show HN: Raspberry Pi3 cluster with Docker/Kubernetes

sweclockers.com

86 pointsnergal23 comments

Translation for those who care:

-------------------

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.

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).

The project consists of:

- 10/100 Mbps switch

- Nexus 7

- 10A 6 port USB charger

- 4 x Raspberry pi 3

- 4 x 8GB SD card

- TP cables + USB cables

- Oak

- Plexiglass

Anyway, you'd all probably rather see pictures than words.

- Nexus 7 with realtime data for all nodes.

- 'Economically' bought 8GB, not class 10, but thinking of running a 2.5" HDD for the controller node.

- Sleeved all the cables, then realised that they didn't fit with the sleeving. Could only strip them and do again.

- First test with 2 x USB hubs that didn't deliver enough current at start-up.

- Flip-up "chassis"

- My modified netdata page showing real-time data for all nodes, including the temperature.

- Running Docker with Kubernetes on the cluster.

-------------------

[Any errors/omissions are my own]

Thanks for translation!

Looks like it could also act as a radiator :) Especially with the RPi 3 heating issues:

https://www.youtube.com/watch?v=e6okZKRwnTQ

Currently waiting for heatsinks that I've ordered. But so far it hasn't reached over 50 C.

Check http://www.pidramble.com/ for a more compact RasPi cluster. Jeff's uSD benchmarks made it to Hacker News front page previously.

Thanks for posting! I'm actually updating the cluster right now, and I have a Pi2 version, a Pi3 version (still in testing, not live yet), and a Pi Zero version (very slow, but same thing is the size of a plum!).

I'll be presenting on it at this year's php[tek], and will also post a few YouTube videos and blog posts about it separately.

Of course it's not as fast as my 5-year-old used Lenovo... But it's great for educational purposes (before anyone starts asking why you'd buy a bunch of Pis when one small laptop beats them performance-wise many times over).

I definitely get the educational appeal. Not just in construction and configuration. This should make a great platform for distributed computing development/testing/experimentation. What is the total build cost of a 6 unit system?

Hrm, if you'd clicked the Wiki in the top header of the link I gave you :) http://www.pidramble.com/wiki/hardware/pis

Curious. Why did you update to the Pi3 instead of the ODROID C2 + eMMC?

Mostly because of the community around the Pi. Interestingly, though, the ODROID C2 may be a much better option. I just don't know if I'll end up picking up more than one of them just yet.

It looks very cool; what does it do? All I'm seeing in the photos is a cluster of 4 PI's that report their statistics to a dashboard.

Will run my game servers for (http://qake.se) in docker containers.

I've long thought about a similar project to test my applications when scaling out and how well concurrency works.

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?

http://www.seagate.com/files/www-content/product-content/hdd...

WD has a customized-for-RPi product.

http://wdlabs.wd.com/products/wd-pidrive-314gb/

Do you know if the Pi2/3 alone (with only a standard smartphone USB charger) can power the WD PiDrive without a USB hub ? It seems like it could but I haven't found any confirmation yet (apart from so SO posts).

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.

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.

I've considered some solution with a small steel-net used for regular computer chassis.

You can get a gauze fabric at like 60p/m. You could make a nice recessed frame to hold it and hide the edge. There's tables online of particle size so you can pick a mesh size.

Got some to use over windows and air vents. Works great and so cheap it's just replaced instead of cleaned. Airflow on the finer sizes would be interesting. Mines a spider guard.

nice woodworking project/nightstand clock.

If you double the rpi number you will get close to used $300 laptop level of performance.

Thanks. I know, but a $300 laptop wouldn't be that much fun to put together like this project was ;)

Very very cool. I love the enclosure!

Reply on news.ycombinator.com