boot from mirrored drive

[Avery_Stiles]

I configured a dell optiplex 260 for raid 0. I managed to install windows advance server on hd 1 and mirrored the second drive. Both drives are configured for dynamic disks. HD1 is set for master and the hd2 is set to slave. If hd1 crashes what would be the best way to boot from hd2?

[TOAD6147]

Does the BIOS offer the option of booting from either one?

[meese]

You would need to change "rdisk(0)" to "rdisk(1)" in the boot.ini file. Below is a sample boot.ini file that boots from the first hard drive 0.

-------------------------------------------------------------
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINNT
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Microso ft Windows 2000 Professional" /fastdetect
-------------------------------------------------------------

You could add another line in the above file. This would cause the os to pause for 30 seconds and you could choose to boot to drive 1, after 30 seconds it would boot to the default drive 0.

-------------------------------------------------------------
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINNT
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Microso ft Windows 2000 Professional" /fastdetect
multi(0)disk(0)rdisk(1)partition(1)\WINNT="Microso ft Windows 2000 Professional" /fastdetect
-------------------------------------------------------------

[Avery_Stiles]

I made the changes to the boot.ini file to reflect to:
multi(0)disk(0)rdisk(1)partition(1)\WINNT="Microso ft Windows 2000 Professional 1" /fastdetect

When I select the second drive from please select the operating system in the first stage of the boot up i get this error message:

Windows 2000 could not start because of a computer disk hardware configuration problem. Could not read from selected boot disk. Check boot path and disk hardware.

[Avery_Stiles]

Well this seemed to work. I enabled the second disk in the BIOS and it booted up after that.

Is there anything else that might need to be configured?

[Peter M]

Besides, RAIDing a master/slave pair of drives is not exactly a bright idea - it cuts write throughput in half. Now since mirroring already does that, you end up with 1/4 of the drive's actual write speed.

This is because on IDE, drives on one cable do not share bandwidth. Access to one drive locks the other one out from doing anything. IDE is not SCSI.

[Avery_Stiles]

What would you suggest?

[Avery_Stiles]

Now i'm testing another theory in this configuration.

When I pull out the first hard drive(master) and make the second hard drive(slave) a master it tells it can't find the drive 0 or 1.

Any suggestions?

[nukes]

Hold on, isn't raid 0 a stripe, no mirror?
If you have set it as RAID 0, you have no redundancy whatsoever if one drive fails. If one drive crashes, you've lost everything off both of them.

[SiliconJon]

If you're wanting to do a RAID 0+1, you want an IDE channel for each drive. And pulling just one drive out of a striped array will make the complete array unusable, resulting in no readable data from the remaining drive(s). that's where the new arrays, like 5, come in handy. They use fancy techniques that allow for a drive in the array to be removed and the data can be rebuilt. 0+1 works similarly, but less effeciently.

So, you had 0+1 on four drives & two IDE channels, is that correct? If so, and you want to benefits of RAID, you're going to need to buy another IDE controller for software RAID, or a real RAID controller (4+ channels) for some real RAID.