Raid 5 failure - please help

Admiral Huddy

Admiral Huddy

Admiral Huddy

Man of Honour
Joined
17 Feb 2003
Posts
29,640
Location
Chelmsford
First time for me..

I have a screen showing that RAID-5 has failed. Continuing the startup process I then get a black screen stating "disk read error".

The system won't boot.

Being RAID-5, I would have thought this would have just downgraded to a single disk config, reporting the disk in error?

My questions are:

1. How can I determine which disk is in error?
2. How can I recover from this?

Any help would be greatly appreciated.

Thanks
 
weird, if it's 3 disk RAID 5 with a single disk down you should be able to run system on 2 disks with degraded performance... at least with a proper dedicated hardware RAID card.

maybe the ICH9R aint that advanced and can't run the system on the fly using the parity stripe (it would need a lot of processing horsepower and I bet it can't do it)

in which case you need to swap out faulty disk and let ICH9R BIOS rebuild the set offline..


above is in theory only.. swap out the wrong disk and you're in trouble :(, but it should indicate from within the BIOS which disk is broken...

if the error was caused by overclocking, reset to default speeds and fingers crossed it can rebuild on your existing disks.
 
Last edited:
Admiral Huddy said:
1. How can I determine which disk is in error?
2. How can I recover from this?
Click to expand...

The matrix RAID splash screen should tell you which of the drives is causing the problem. If not then a quick Ctrl+I will take you into the RAID utility itself which should give you some more info. It is a bit wierd that the system won't boot with the array in a degraded mode, are you sure it's just one drive that's marked down?
 
Admiral Huddy said:
I have no idea at this point.. I'm trying CTRL-I to no avail.
Click to expand...

That is indeed the correct key combination, you may not be getting the info or option on the screen if the bios is set to quick boot or is being masked my a manufacturer splash screen. check these options in the bios.
 
First thing I would do is make/break all the connections (replacing the SATA cables would be good). Are any drives making silly noises on spin-up?

If you can't get into the RAID BIOS with all drives attached it may be that just one has physically failed, but in such a way it's preventing the others communicating. So, take one drive at a time out and re-boot - if that doesn't work move on to the next and try again. Hopefully that will locate and remove the bad disk and allow you to access the BIOS.
 
Last edited:
i just had a thought

if your BIOS had reset for some reason (sometimes they can), motherboard would go 'out of' RAID mode into normal SATA.. hence your RAID BIOS not appearing / letting you in. Also why your PC not booting.

go into main BIOS and ensure your controller is in RAID mode...

just a idea... if this is the case your PC will boot just fine after doing this :)


edit: oh forget it, you said raid bios appears fine in first post.. I'll shutup lol
 
ehh you have a very very good point good point.. I'll check that later anyway as the RAID menu is no longer appearing.. I think the the user pressed F2 to for safe CMOS settings..???
 
Ok, The RAID menu shows raid set as failed but all 3 drives are green and ok.

There was an option to Repair Raid Y or N so i selected Yes.

The status has gone to "Rebuild" with a message saying it will be rebuilt within windows?

Managed to boot into windows but everything incredibly slow..

I've also done a quick scan using HDD tune and it reported no errors.

Any ideas as why the machine is so slow?
 
Admiral Huddy said:
Any ideas as why the machine is so slow?
Click to expand...
If it's rebuilding the array then a) it's hammering the disks so any I/O is going to be fighting that and b) it's recalculating the parity which will be using all the CPU.

For 3x500Gb you're looking at a good few hours to do the rebuild
 
rpstewart said:
If it's rebuilding the array then a) it's hammering the disks so any I/O is going to be fighting that and b) it's recalculating the parity which will be using all the CPU.

For 3x500Gb you're looking at a good few hours to do the rebuild
Click to expand...

thanks rp - so this is normal whilst it's doing the rebuild?
 
Yeah, that's normal behaviour for a rebuild. It sucks but at least you can do it online, the first RAID controllers I dealt with made you sit in the RAID BIOS while they built the array.
 
How long can I expect the rebuild to take? I've booted to desktop and since 9am this morning and things are still very slow.

Is there anyway in Windows I can find out when it's complete or monitor it's progress?
 
Last edited:
Well I left the machine on for 24 hours and the status changed to "ready" the next day and all is ok now. I still have no clue as to what went wrong but it seems to have corrected itself.

Thanks for the help
 
Sometimes if your PC crashes (i.e. hard freeze or BSOD) it can invalidate the array and cause a rebuild.

I have witnessed this a couple times on friends PC's who have RAID1.

In all cases the Intel Matrix RAID did a rebuild (although automatically, not sure why yours needed to be pushed to do it! :confused:) and this resulted in a very slow PC for many hours.

Although if your PC is crashing in such a way in the first place then you can pretty much expect data integrity to be compromised...!
 
You must log in or register to reply here.
Back
Top Bottom