HostRaid support on FreeBSD

[Maxim Sobolev]

Dag-Erling Smørgrav wrote:

> Maxim Sobolev <sobomax at portaone.com> writes:
> 
>>Well, my knowelege about internals of software RAID controllers is
>>quite limited, but as long as I know they are no more than BIOS with
>>UI for setting up RAIDs and interface to main BIOS that hides internal
>>RAID structure allowing to boot off the RAID. Also they provide some
>>persistent storage for RAID configuration, I assume either in some
>>controller's NVRAM or on the HDDs.
> 
> 
> The configuration is always stored on-disk, otherwise it wouldn't be
> possible to recover from controller failure.
> 
> 
>>Therefore, the same set of GEOM
>>RAID modules can work with different software RAID controllers (SCSI,
>>ATA, SATA etc) if there will be a standard way to extract this info
>>from the controller's driver, and present it in some common
>>format. That's what I am talking about.
> 
> 
> You're kicking down open doors.  This problem has already been solved
> for Vinum, which is conceptually identical from a GEOM point of view.

Nah. As I said there should be some standard way to extract RAID 
configuration info out of controller's driver in controller-independent 
format.

-Maxim