"How to dismantle and manufacturer's RAID array"

[rschilling]

When I tried to install fedora13, f13's installer kept seeing my hard drives
as a "BIOS RAID set (mirrorred)". Ubuntu10.04's installer had the same problem with
my drives but that installer was less informative than f13's installer. U10.04's installer
just stalled in the first screen, the one with the word Ubuntu above five dots, giving no hint
as to what it didn't like.

My pc came from Dell with 2 identical SATA hard drives in a RAID level one array.
I changed CMOS settings from "RAID ON" to "ON" for each hard drive.
That did not dismantle the RAID configuration, at least not
in a way that satisfied f13's installer.

I reinstalled xp and tried to install f13 after a minimal xp installation.
f13's installer detected "BIOS RAID metadata."
What is it that f13's installer is detecting?

I thought this might have something to do with nVidia's nForce4 Serial ATA RAID controllers. These are installed when you install the version xp that came with my system, not like most other drivers which you install after xp. I contacted nVidia but they
couldn't help me with this.

Well, it turns out to be Dell's fault. They place this "BIOS RAID metadata"
in a special place on each hard drive of a RAID set. It survives even the formatting that accompanies a reinstallation of xp.

If you want to truly dismantle a manufacturer's RAID set, you must use software like "dban" (www.dban.org) to thoughly wipe clean the drives.

Download dban, burned it to a cd, then boot that cd. dban's auto??? command didn't work
for me but its dod command did the trick. The process took aout seven hours for each of my 160gb hard drives.

Hey, i was real impressed by the help i got throughout all the twists and turns that took this problem far away from the original statement Special thanks to Scotty38
and to the "Troy Polamalu looking" young man working at Best Buy here in Little Rock, he understands how manufacturer's are shipping their pcs.

Randy

[David Batson]

AFAIK, this is usually done from the BIOS menu or similar menu at boot time. Look in the BIOS menu first. If you don't see anything there, try setting your BIOS to boot in Diagnostic mode and look for any messages displayed (before the OS boots) regarding pressing a hot key to enter the Raid setup.

EDIT, on rereading your post I see that you were posting a solution, albeit not the customary one.

[rschilling]

Changing BIOS settings may not completely dismantle a RAID array.
As i said in my previuos post, you can change the "RAID ON" CMOS (BIOS) setting to "ON" for each drive of a RAID array, but f13's installer will continue to find "BIOS RAID metadata" on your drives and the installer will treat your drives as a mirrored pair. If you choose to complete the installation of f13, the installation will effect both drives, causing you to loose data that you expected to be unaffected by the installation.

[droidhacker]

You could do it the easy way instead of downloading weird software.....

dd if=/dev/zero of=/dev/sd? bs=1024 count=1000000
* that'll zero out a big chunk at the beginning of your disk.

Also the "dmraid" command has the option to delete fakeraid metadata. You can use the "-E" option.