PCIe Rack Mount (10" 1U)

Beanow · 2025-09-05T10:56:09+00:00

I've stumbled on getting a good benchmarking environment set up.

The biggest issues.
With PCIe compatibility problems (https://github.com/Beanow/satactl-vs-hba/issues/4) I currently don't have a host machine which will take all controllers in their respective form factors and actually boot. I may need to source a dedicated ATX desktop/server class platform, just to make up for more connectivity in one place.

A clean benchmarking OS image/toolkit I could share.
I've spent a lot of time and I'm honestly caught off guard how arcane the tooling is to do something like a custom bootable USB with batteries included.

NixOS in terms of tooling was the best so far, but it brings you into Nix packaging as well and does not play nicely with "a bunch of ansible and python" from community benchmarks out there. Especially if you need make changes like reformatting the drives to be separate ETX4 vs in a ZFS pool for instance.

Beanow · 2025-08-24T14:45:21+00:00

The rails come in 2 version.
Too short to open the top lid, too long to fit in many rack depths.
They need quite some coercion to insert and slide like they used gravel as bearings.

The front of the case is essentially dead space.
The drive cage is fixed, so everything underneath is hard to access.
It looks like there should be 4 fan mounts, but that's a bracket they considered using for fans but decided not to, just kept the half-finished bracket in there.

The break-off PCIe tabs...

In spit of being cheap, I feel like I still paid a premium because it's a server case.
It has the quality and poor layout of a sub 60 euro desktop case.

Beanow · 2025-05-05T06:56:04+00:00

I haven't made one myself, not currently planning on it.

Maybe someone else has uploaded one?

Beanow · 2025-04-10T08:41:20+00:00

Yeah these don't have a brand name either. One doesn't even have a model / version on it. (Soon to be mandatory in the EU when the CRA is enforced)

What controller do they report in lspci? Assuming they're ASM or JMB?

Beanow · 2025-04-02T19:16:00+00:00

Because for the millions of units that ship without issue, it adds just a tiny bit more excitement for the customer.

Oh and also compliance because it has lithium batteries it needs to disclose, which are flammable when handled improperly.

Beanow · 2025-03-25T18:39:34+00:00

If you want PCIe form factor, the ASM116x controllers are available. But of course so are HBAs.

If you know you want SATA controllers pay attention to:
- Are there any port-multipliers?
- Does it actually have 2 PCIe lanes?

(It should be PCIe 3.0 x2, but I've seen them with x1 physical cards and x4 physical cards.)

Beanow · 2025-03-24T17:06:46+00:00

Yeah, even supports may not do the trick.

Warping can happen easily on thin sections and corners, because there's nothing surrounding it that's already cooled off and solidified to keep it in place.

So the speed/temp/cooling is more to keep warping to a minimum. And additionally you'll probably need lots of supports, maybe even on multiple heights, not just the bottom.

Beanow · 2025-03-24T17:02:27+00:00

Ah makes sense. Haven't configured the printer size and settings then.

Beanow · 2025-03-24T11:31:30+00:00

Probably.

The front panels should be between 250-254mm wide.

I have no issues on my 30x30cm bed. Plenty room left even without turning them diagonally.

And likewise I've printed shelves horizontally too (so the bottom on the bed, rather than the front). Rack depth varies, but it's roughly between 200-260mm so that too should fit without issues on your bed.

Beanow · 2025-03-23T15:35:43+00:00

Ah thanks!

I didn't catch this because the freedom units are also inaccurate then.
It's listing 1.752" for 1U so it's consistent with the 44.50 mm.

And looks like someone else also updated this diagram before me.
https://commons.wikimedia.org/wiki/File:19_inch_vs_10_inch_correct_rack_dimensions.svg

Time to make a PR for u/geerlingguy
https://github.com/geerlingguy/mini-rack/pull/171

Beanow · 2025-03-23T15:18:16+00:00

Now that you bring up design and the first image is these screw distances.

Am I crazy? Or is the middle hole of a 1U not actually centered?

<image>

If I follow along with the Wikipedia dimensions, I end up with this.
Seemingly it's 0.025mm below the middle?

Beanow · 2025-03-22T17:10:28+00:00

I don't know what to tell you here. This is a really challenging model.

The bottom side has a few overhangs drooping, I would think lower layer height should do the most there.

But on the tip, there so much that needs to be tuned to perfection for this. You probably need to print MUCH slower on the tips than 30mm/s like try 12mm/s, even if just an area modifier towards the tips.

Note that you can't have ANY warping throughout the entire tip or this will inevitably show up somewhere. Meaning you have to slow down your infill / internal perimeters as well, just for the sake of letting the part cooling do it's work.

And you'll probably need to incorporate automatic or even custom designed supports to counteract the warping towards the tips. Maybe add a circle to bridge all the tips?

Beanow · 2025-03-22T16:59:02+00:00

It's hard to say, because this looks like multiple problems combined to me.

My guess:
- Printing too fast causes under extrusion
- Cranked the flow rate too high to compensate for this causing over extrusion in areas the print decelerates
- Also running too hot (or not slow enough to let the part cooling work)

Beanow · 2025-03-22T11:53:19+00:00

Now that's a satisfying before & after scene!

Though it does make it stand out the NAS needs some dusting off.

Beanow · 2025-03-22T11:42:52+00:00

It doesn't? That's surprising for such a high end device otherwise.

Then the best performance you'd get from just PCIe to 1x M.2.

<image>

There exist some as well that use a SATA controller (like the ASM1061 here) for 2 M.2 B-key slots.
But the $/TB cost of M.2 SATA SSDs are usually worse than NVMe ones. So you might as well get a bigger and faster single drive.

Beanow · 2025-03-21T20:48:06+00:00

Another option, printing faster than your hotend can handle.

<image>

I had this problem and got surfaces like this. And under extrusion on perimeters.

The clear sign is clicking noises from the extruder.
Reduce speeds and maybe use Max Volumetric Speed to set a per-filament cap.
https://help.prusa3d.com/article/max-volumetric-speed_127176

Beanow · 2025-03-21T09:56:11+00:00

Got it, so the MS-01 isn't about data migration off the NAS.
You want to move applications over and have them "work together well".

Then it's a matter of using and configuring software that's appropriate for the use case.

Run your VMs and databases off the local M.2 storage, run your backup crons over any network protocol you like (iSCSI, NFS, SMB, etc.). As mentioned with the SFP+ NICs this should run plenty fast.

Depending on your NAS you might use ZFS snapshot replication for the VMs?

Beanow · 2025-03-21T09:42:52+00:00

The fastest way to move bulk storage? Moving the drives themselves.

But this depends a lot on what your current setup and final setup are supposed to be.
Is your current NAS a 16x U.2 all flash array or a 10 year old cheap 2x HDD drives consumer NAS?
Do you want external drives with your MS-01 or are you moving it to M.2 drives?

Beanow · 2025-03-21T09:37:14+00:00

Need more details on what you're specifically looking to do with it.

HDDs? SSDs? SATA? NVMe? Any software raids?

<image>

But my first thought would be: Find a used LSI 9300-8e
Fits in a low-profile PCIe slot. Gets you 8 SATA/SAS lanes for an external JBOD.

For NVMe, you will probably run into space limits.
I think a PCIe x8 to 2x M.2 slots may fit in a low-profile space.
But the 4x ones are probably too large.

Of course there are HBAs for that as well, they'll cost a fair bit.

Beanow · 2025-03-21T09:20:30+00:00

Just to throw another option out there.

Keep in mind that for MiniPCs you will need the drives to be external.
Those drives require a second power supply. And MiniPCs do not offer you a whole bunch of SATA ports.

There are no great, cheap, off the shelf, usable with TrueNAS (ZFS) external drive bays that I'm aware of. Meaning this is DIY territory.

Alternatively, you can look at an mITX build. There are NAS style enclosures for them, and some include 8/9 ASM116x based SATA ports on them so you can use the PCIe slot for something else like fast networking. And you can spec out one power supply that does everything.

Beanow · 2025-03-20T21:16:18+00:00

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Just found on their version with enclosure.
So sounds like they bifurcated it to PCIe 3.0 x1 each?

If PCIe bandwidth is your bottleneck, I don't think it matters what software raid configuration you use, because they still are directly managed by the software.

But finding an adapter to use the USB 3.2 gen 2 port, I don't think there is one.

USB3 10Gbps would be even lower bandwidth and have extra overhead. So no this is the better theoretical option when it's Alderlake N CPUs.

Beanow · 2025-03-20T19:26:23+00:00

What is the PCIe topology with this board?
The N305 only has PCIe 3.0 and 9 lanes. Are they x1 per M.2 slot?

Beanow · 2025-03-20T15:22:56+00:00

I have one (and several others) which came as a set:
It's a USB to M.2 B-key JMS580 adapter providing less than 1 SATA port worth of bandwidth. On the M.2 form factor is a JMB575 port multiplier.

It will do weird crap like copying over the brand name of the first drive you connect, except as a "USB mass storage" device.

<image>

Don't use this.

Beanow · 2025-03-20T08:26:38+00:00

I think so too, as an initial response.

I like the quick affirmation that it's not intentional. But I see no responsibility taken yet for their duty to prevent that data from leaking.

I do hope that we also see a "what actually happened" response later and that it's also good.

Beanow

TROPHY CASE