Good luck getting a hw raid vendor (other than 3ware) to help you :-)
-----Original Message----- From: centos-bounces@centos.org [mailto:centos-bounces@centos.org] On Behalf Of Ignacio Vazquez-Abrams Sent: Thursday, September 08, 2005 10:46 PM To: CentOS mailing list Subject: Re: [CentOS] Installing on Abit BE7-RAID
On Thu, 2005-09-08 at 19:26 -0700, Todd Cary wrote:
I have RH 8 running on a Abit BE7-RAID motherboard. My task is installing Centos 4.1 with limited knowledge on installing with
hardware
RAID. The arrays are still in place for the two pairs of drives.
HighPoint only shows drivers up through RH 9.
Will the drivers work with Centos 4.1?
Absolutely not. The kernel versions are far too different. Contact HighPoint for updated drivers.
Will I be able to ue software RAID?
Todd
Drew Weaver wrote:
Good luck getting a hw raid vendor (other than 3ware) to help you :-)
-----Original Message----- From: centos-bounces@centos.org [mailto:centos-bounces@centos.org] On Behalf Of Ignacio Vazquez-Abrams Sent: Thursday, September 08, 2005 10:46 PM To: CentOS mailing list Subject: Re: [CentOS] Installing on Abit BE7-RAID
On Thu, 2005-09-08 at 19:26 -0700, Todd Cary wrote:
I have RH 8 running on a Abit BE7-RAID motherboard. My task is installing Centos 4.1 with limited knowledge on installing with
hardware
RAID. The arrays are still in place for the two pairs of drives.
HighPoint only shows drivers up through RH 9.
Will the drivers work with Centos 4.1?
Absolutely not. The kernel versions are far too different. Contact HighPoint for updated drivers.
On Thu, 2005-09-08 at 20:01 -0700, Todd Cary wrote:
Will I be able to ue software RAID?
FRAID _is_ software RAID. It just typically uses the FRAID vendor's driver, instead of the OS.
Newer kernel 2.6 developments with Device Mapper (DM) are now able to read some of the reverse engineered, proprietary FRAID disk organization and interpret it. Once that is done, the DM implementation can use the software RAID in the Linux kernel to drive the disk organization -- and much more efficiently than the FRAID implementation.
FRAID is _rarely_ faster than the OS' native software RAID. And vendors can _rarely_ offer FRAID drivers for Linux, because they contain proprietary code for the RAID licensed from 3rd parties. Hence the continued problem, and the need for solutions like kernel 2.6's DM.
Unfortunately, FRAID models vary in their disk organization, so you can't always trust these reverse engineered developments. And then you have the whole kernel volume/software stack, which has race conditions, etc... that I just don't trust at this point. But I won't go there.
On Thu, 2005-09-08 at 22:47 -0400, Drew Weaver wrote:
Good luck getting a hw raid vendor (other than 3ware) to help you :-)
FRAID is _not_ hardware RAID. There is *0* hardware on-board. It's a 100% "dumb" ATA controller, with a trick BIOS for 16-bit Int13h disk services, and then a trick driver for the OS that has 100% of the RAID logic. It uses your CPU for 100% of the activity -- even when you are targeting the volume, the raw drives are still visible by the OS.
3Ware _is_ a true, intelligent hardware RAID -- on-board ASIC + SRAM.
From the standpoint of your CPU, it's just sending a stream of data to
the ASIC, not the drives. It can't even see the drive or communicate with them. This is a _core_ difference between FRAID and intelligent hardware RAID.
-
Bryan J. Smith -
Drew Weaver -
Todd Cary