M.2 U.2 (Mini SAS HD) and FreeNAS

[ElkossComb]

Hello guys
I was thinking of building my new NAS setup. I find a nice case in 2u format with 12 trays in front for my rack, I already have a recent motherboard with a Xeon on it and a M.2 port
As the HDD backlane of my case offer only a Mini SAS HD connexion, I was thinking about plugging an M.2 to U.2 adapter (which is specified as Mini SAS HD standard port by the manufacturer)
I want to put FreeNAS on the system, so buying an expensive Raid controller with SAS embedded port is not in my mind since it's expensive, and not recommended for FreeNAS OS.

Do you think this connection will work / will be suitable? If not, have you a smart solution to my connection issue?

I don't have any information about compatibility, just the Mini SAS mention on this adapter! (https://www.newegg.com/Product/Product.aspx?Item=N82E16813998031)

Thanks in advance

 

[danb35]

I want to put FreeNAS on the system, so buying an expensive Raid controller with SAS embedded port is not in my mind

How about getting an inexpensive SAS HBA? That's normally the recommended course of action.

 

[Ericloewe]

I don't know what you're planning to do, but I do know it won't go as planned.

If you're thinking of using PCIe SSDs with the M.2 port, cost will quickly exceed that of an SAS HBA plus SATA/SAS drives - if you can even find the parts.

If you're thinking of plugging the U.2 connector into the SAS backplane, you'll accomplish absolutely nothing as the PCIe controller on the motherboard/CPU has exactly zero knowledge of SAS or SATA. You'd need an LSI SAS 9400 and a backplane with an SAS expander/PCIe switch combo device to even approach the sort of flexibility you're dreaming of - you guessed it, it would cost you a pretty penny.

 

[Arwen]

As @Ericloewe wrote, that device appears not to be actual SAS, but a PCIe pass-through using a SAS connector, probably for fancy flash drive(s).

How about you tell us about your system board, disk backplane and model of disks?

It's possible you could get by with a reverse break out cables, (4 x SATA ports on the system board, Mini-SAS on the disk backplane board). If so, you would need one cable per 4 disks you intent to use.

 

[ElkossComb]

I explained the list of connectors in the first message: Motherboard;M.2 to U.2 adapter >>>> Mini SAS HD on backplane >>>>> HDD Sata
But I get the point
My initial question was to know about the possibility of this Connection, I know alternatives!
Thanks anyway :)