The Raspberry Pi single board, all of its versions, are actively used by both professional network equipment developers and amateurs. One of the most popular areas is the creation of servers based on "raspberry". At the beginning of the year, a description of blade servers based on the Raspberry Pi 4 Model B appeared on the network.
As it turned out , these systems are being developed by the user Habr ww898 for his company. They are used as CI for TeamCity. The third generation of this server is now presented. A special rack accommodates 14 single-board devices and the same 2.5-inch SSD.
Features of the third generation server:
- Increasing the number of single-board devices to two racks.
- Reduced printing time and plastic consumption.
- Reduced assembly and disassembly time of the server.
- Reduced number of parts.
- Modular design, so the MARK III will be available in a variety of modifications.
A 3D model of the rack is available here .
It is clear that you will not be able to print absolutely everything, you need power supplies, coolers, screws and so on. Here's a complete list:
- A set of 5 coolers, the developers used the Arctic F8 Value Pack.
- Power supply for coolers 12V2A 7Tipps.
- Adapter for 1-6 coolers - Lüfter Adapterkabel 3Pin auf 6x 3Pin Molex.
- Cooler screws, M4 12 mm - 10 pcs.
- Threaded rod M5 ~ 452mm 2 pcs. and 4 nuts M5.
- 20 screws for attaching coolers (usually included).
- 2 pcs. M3 ~ 5mm for each SSD.
- Adapter for SATA, USB 3.0 to SSD.
Each single board in the rack is powered by the official Raspberry Pi (PoE) HAT. SSDs are connected to the system using the adapter mentioned above.
The project started in April this year on Thingiverse - the developers have improved the model they found there. We adapted it for our own needs and scaled it to fit eight raspberries. And then they posted their own model, which quickly became popular. The authors of the project plan to develop it further.
What can you use such a server for?
The developers created it as a CI for TeamCity. But of course there are other possibilities as well. For example, last summer, developers at the Raspberry Pi Foundation decided to create their own server for their site and successfully completed the plan. To do this, they put together a cluster of 18 fourth-generation "raspberries" with a quad-core 1.5 GHz processor and 4 GB of RAM.
A cluster of 18 Raspberry Pi 4. Source: raspberrypi.org
The company was gradually shifting traffic from "normal" hosting to new hosting from the Raspberry Pi. Everything went well, the equipment survived. The only nuisance is the failure of Cloudflare, the blackout lasted two hours. There were no more failures. The hosting worked without any problems for a month, after which the company's website was returned to its usual virtual environment. The main goal is to prove that the server is efficient and can withstand a high load (over ten million unique visitors per day).
