Homelab

SAS is not networking. If you expect to connect 2 systems to another it wont work.

If its just for disks then yes.

Yes, I have a very similar setup for UNRAID, two separate rack mount cases just for HDDs that link to the head unit over SAS

I really get turned off when people post a picture and walk away with little to no detail. What are you trying to accomplish?

This looks wrong, why not just use something like a LSI 9200-8e and skip all the swapping.

There’s literally a JBOD version of those supermicro cases

Love the graphic

Thanks to everyone who answered. I didn't provide any details because as the saying goes, one picture is more than 1000 words worth..

Yes, the "System 1" is a JBOD with a SAS/SATA 16 Ports backplane, that will run a mix of sata/sas/ssd's hard drives. This must go with no witchcrafting to the "System 2", as .. pictured.

I also consider a 4 x 8644 external HBA, but until now I only managed to find some LSI/Broadcom/Avago cards that are too hot and maybe fake chinese ones, with no guarantee of data/firmware/functionality. And the prices are also too high.

I,m already over my buget.

Yes, this should work fine. SAS does not care what path the signal takes - it doesn't differentiate between internal and external. You can run internal over external cables without issue. I've done similar by turning my old NAS chassis into a DAS, and connecting it to her internal ports of the HBA. And you can connect SAS or SATA drives to the DAS (system 1).

This would work but backwards.

Since system 2 is the one with the raid/HBA card I assume that would house your brains.

Looking at the end-product, 16x SATA connections. It would be a waste of cables/money to do it the way you pictured.

It would be sufficient to run a single 4e 8644 port from system head to JBOD, there you could use an expander to achieve the 16i needed. This way you would have 6Gx4=24G/3GB or ≈250MB per drive. Could do the same with 8e, point is you are maxing out the 12 drives with 4e don’t need 16e and associated cables.

Depending on your future needs you could go with 8e/16e in the head and have those extra ports in case in the future you want to add another JBOD (1 per 4e).

PS since you head appears to have drives, you should source an external card from the get-go instead of an internal to then connect cables to an external converter. I’m assuming you pictured an additional card and not the one running those disks.

Hope that was clear enough.

🍻

Unless you already own all of these parts, acquire an “-8e” HBA for your “System 2” and install an expander in “System 1”. Many expander cards only draw power from the PCIe slot connector and are suitable for use in a JBOD chassis.

There are a loooot of connections in here so many points for failure, and a lot of money spent on cables

Yeah, you are basically just making a DAS there I guess

[Update]
I managed to do some preliminary test, by connecting 4 drives (2 x SAS, 1 x SATA3, 1 X SSD SATA3) as pictured.

I have tested using an Adaptec 71605 (4 x 4 8643 ports) and found some strange "happenings".

When connected directly into the Adaptec card, all seems fine. But when connected through the AOM-SAS3 external 8643 to 8644 adapter, the SSD SATA3 strangely "drop" to 3.0 Gb speed, although the SATA3 HDD remains at 6.0Gb:

https://imgur.com/a/KDm4AdI

Now this is really strange.

I'm also found a 8644 16e 12Gb HBA card that must arrive. I will update the post