Controller for ZFS

[Borja Marcos]

On Nov 13, 2013, at 7:41 PM, Shawn Wallbridge wrote:

> I was wondering what the preferred/best supported 24port SAS/SATA
> controller is for FreeBSD? I have a box with a LSI/3Ware 9750-24i4e in it,
> which I can use in JBOD mode, but it seems like a waste to me.

Not only a waste, but a serious problem.

You absolutely do not want a "JBOD mode" in which you create so-called RAID0 1-drive logical volumes.

You absolutely do want a silly and stupid HBA which just passes SAS/SATA  commands from the OS to the drives
and back. 

The "JBOD mode" offers a fake device in which the "intelligent" controller makes its own decisions and, of course, hides
the very important SAS/SATA status codes from the OS.

ZFS knows better. 

The one I use is sold by Dell as the "H200". They usually try to disuade you by saying that it's not intelligent, doesn't
offer RAID, some of their "configuration aids" even forbid it... I just tell the salesman to shut up because I know much better than him.

The only problem: beware if you are using a built-in backplane in the server, some manufacturers insist on using different
cabling schemes for different controllers and you could run into stupid problems because of that.

FreeBSD 10 identifies one of my cards as this one:
mps0: <LSI SAS2008> port 0x7c00-0x7cff mem 0xd4ff0000-0xd4ffffff,0xd4f80000-0xd4fbffff irq 80 at device 0.0 on pci67
mps0: Firmware: 07.15.08.00, Driver: 16.00.00.00-fbsd
mps0: IOCCapabilities: 185c<ScsiTaskFull,DiagTrace,SnapBuf,EEDP,TransRetry,IR>








Borja.