Building a mini cluster – Part 10: Adding the finishing touches

Another few weeks have gone by and since the last update, the mini cluster build has been completed.
Before anything else, let’s go through a few photo series detailing the most interesting parts of this final stretch.

Buttons,button, buttons….

Every serverboard has two push buttons connected to it: a large 19mm power button with a circular power LED and a 16mm reset button with a dot LED showing disk activity. With 6 motherboards in a chassis, that makes for twelve buttons and 24 cable pairs. Suddenly, that’s a lot of cables!

Connecting the Hard disks

Now that the buttons are all cables up, the last components to add are of course the hard disks.
On these motherboards, the power cable for the SATA disk also comes from the motherboard. I am using the cables that were supplied with the boards even though they are a bit on the long side.

As is p(l)ainly visible on the images below, I seriously under-estimated the SATA cable management needs for this build…  The server boards are only about 5mm beneath the ridges where the disk plateau will rest. It took quite a bit of massaging the cables to get everything to sit comfortably.

But in the end, with the application of some “strong persuasion”, I was able to set the disk plateaus in place.

A Finished Compute Pod

Finally, after all this time, the green compute pod is completed!
The horrible cable mess is clearly visible through the transparent acrylic…
Lesson learned!

A view from the back

Now that all pods are completely assembled, time to cable everything up.

Even though there is still somewhat of a mess with all those network cables, I am actually quite happy with the result here. A single power lead goes from the power pod to each compute pod to provide all the needed power and all the server board IO ports are easily reachable. I like it!

The white numbers on the blue pod were not planned, but when I peeled off the protective plastic from the acrylic, these numbers stayed behind and I kind of like the effect.

I did foresee two power sockets on the compute pods: the second unused hole is there in case I want to add some extra LED lights in the cases, and I would want to be able to switch those lights on and off, independently of the servers. However, considering the cable mess already present, I do not think I will go for it. Still: it’s always good to have options.

The final result

And here it is, the finished mini cluster:

LED’s make everything better!

After-Build Analysis

When I started this project, I was fully aware there were going to be a lot of new things to learn. I have never been a DYI kind of person and with 20/20 hind-sight, I would certainly do certain things different now. That begin said, I am actually quite pleased with the end result: the cluster itself performs very well and using the acrylic really makes it a nice thing to look at too!

For anyone who is thinking about doing something similar, I would say: “Go for it!”

Some parting thoughts:

• The acrylic is very nice and easy to work with, though expensive
• Drilling aluminium is slippery: get a good drill stand
• LEDs are FUN!
• Those magnetic fan filters really work well and look good to boot!
• If using crimp-on cable leads, invest in a good crimping tool (I now wish I had)
• Do not under-estimate the space you need for cable management
• Shopping around really makes a difference
• Try to get everything in as little shipments as possible

Total Spend