UnRaid OS 12gb/sec. transfer speed support?

[binar]

Fellow Forum Members,

I have a Supermicro X10SRH-CF motherboard. I am setting up a UnRaid Cache Disk using two 2TB Crucial MX500 SSD drives setup as RAID 1. Is the SUPERMICRO AOC-USAS2-L8i card shown below compatible with the UnRaid OS?  The card claims a transfer speed of 6gb/sec. For a lot more money I could buy the Supermicro AOC-S3008L-L8I which claims a transfer speed of 12gb/sec.  Is the UnRaid OS capable of supporting 12gb/sec. transfer speeds? If no, then I will just save my money and buy the card with the 6gb/sec. transfer speed.  If anyone has a recommendation for a better card please share. Any opinions welcome.

 

Edited May 26, 2020 by binar

[Frank1940]

A proper line of inquiry would be this.  A 6Gb/sec card will be able to send 750MB/sec to the drives connected to it.  Now how many drives can you hang onto this card?  (Most of the time, the answer will be 8 drives.  But it is possible to actually have more.  This is the real reason for the existence of the 12Gb/sec card.)  IF all eight drives were active at the same time doing independent read and write, the data transfer rate for each drive would (ONLY!) be 93.75 MB/sec.  Most large HD's will easily exceed this rate (on large size files) and SSD will be well above this speed, so one could make a case for the 12Gb/sec card.  (If you had only four drives of the eight active at a time on a 6Gb/sec card, the transfer rate would be 187.5 MB/sec.)

 

Of course, the problem is that the typical use case for Unraid does not suggest that this high data rate is really necessary.  You would probably have a rough time constructing a use scenario where this would be required.  It would also some considerable to given to getting data in-and out of the server.  You would probably need a couple 10Gb network cards and commercial network switch to properly link these cards together.  There is a lot of thought required and engineering required if you truly require extremely high data transfer rates.

 

Edited May 27, 2020 by Frank1940

[JorgeB]

10 hours ago, binar said:

Is the SUPERMICRO AOC-USAS2-L8i card shown below compatible with the UnRaid OS?

That's a RAID controller (though it might be flashable to IT mode) better to use any of the recommended LSI HBAs instead.

 

10 hours ago, binar said:

Is the UnRaid OS capable of supporting 12gb/sec. transfer speeds?

Yes, but only SAS devices support 12Gb/s, SATA is still 6Gb/s max.

[SundarNET]

From your main question I assume you are new to UNRAID OS, you NEVER want to use ANY type of RAID controller to connect your drives to UNRAID. always use a normal controller non RAID or HBA in regards to SAS controllers 'and always check the compatibility lists' this way the HDD info gets passed through to the UNRAID OS and you get direct access to the HDD's and you would then use the URAID OS to assign your SSD drives as the cache drives and URAID OS mirrors them itself. this is the only way you should use drives in URAID, I have tried the other way with RAID controllers and it is a nightmare, it is also pointless its in the name of the OS itself ' UNRAID ' as the OS does away with the need of RAID controllers as well as allowing easy retreival of data from a broken array/install .... and so on

personal notes 

I currently have a Dell R910 rack server with  LSI SAS2008 HBA internal SAS controller as well as an external one for my MD1200 storage array, these have in total 23 drives, 2 1TB SSD for my cache 2x3TB WD RED SATA parity drives then 19 more drives most of them SAS drives ranging from 2TB 1.8TB and 1.2TB, reaching a total of 29TB. the current issues I am having is I think the MD1200 wont mix and match SATA and SAS drives and I might need faster controllers eg 12Gbps as it takes 22 odd hours for a parity check ouch!

[SundarNET]

https://www.ebay.com.au/itm/Genuine-LSI-6Gbps-SAS-HBA-LSI-9200-8i-9211-8I-IT-Mode-ZFS-FreeNAS-unRAID/153224272841

 

https://www.ebay.com.au/itm/OEM-LSI-9300-8I-PCI-Express-3-0-SATA-SAS-8-Port-SAS3-12Gb-s-HBA-Single/173708301179

 

top one is 6Gbps bottom is 12Gbps

these might work not fully shure always check the compatibility lists

Edited May 27, 2020 by SundarNET
info addition

[Frank1940]

4 hours ago, johnnie.black said:

That's a RAID controller (though it might be flashable to IT mode) better to use any of the recommended LSI HBAs instead.

I actually downloaded the manual for the manual for the AOC-USAS2-L8i/L8e and found the following in it:

 

It appears a bit confusing (at least to me) as to whether it is in the IT Mode out of the box or requires flashing to that mode, but the card spec's definitely indicates that it will work in that mode.

 

[binar]

Thank you to all for your posts. Correct, I am a newbie as it relates to setting up an UnRaid system. And I am glad I checked before buying a PCI addon card that most likely was going to end up being incompatible with my UnRaid OS.  I plan to spend more researching the details relating to the addition of a Cache Disk after the UnRaid array has already been setup.