Raid Array

Seekermeister

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I just got back from the store (PC Club), where I intended to exchange a couple of items, but struck out on both counts. I want to verify what I was told on one of them...a Maxtor/WDC combination. My current array is two Maxtors, but due to some smart errors, I need to replace one of them, which is what I bought the WDC for. When the WDC is installed, the system will not boot at all, regardless of which drive it is paired with.

The information that I got at the store was vague and uncertain, until a technician told me that both drives had to be an exact match, for the array to work. I knew that they needed to be the same size, and I could understand if there was some fundamental difference between them, but he said that they not only had to be similar, but the exact same brand and model. I have discussed this a number of times in the past , and no one has ever told me this before...is it true?
 

Fullmetal Chocobo

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No, it is no true. You can use different drives; hell, you can actually use different sized drives on some controllers, but it might be recommended that you use the same drives. There is no reason why the drive being a different brand wouldn't cause the computer to boot though.

Are these SATA drives or IDE?
 

Seekermeister

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SATAs. The first store clerk said that it was because that the new drive wasn't formatted. But since it's not possible to format a drive unless you can boot, I was confused. So he tested the drive and said that it was okay. He also formatted it while checking it out. If the format was the problem, then I guess that I will just have to install it to find out.

EDIT: I guess that it could have been formatted using the repair function, but then I guess that it would have been necessary to disable the raid array...or would it?
 

John

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Here we go again with the minimum wage workers giving out incorrect information. :p You can use different speeds/brand/size for raid arrays but you are limited to the performance and capacity of the smallest drive.

Format was not the problem with your WD drive. If you can't boot with the drive connected it is a hardware issue. You have to be able to let the bios see the drive before you can partition and format it (unless of course it has already been done on another system). Did you try jumpering the WD for SATA 1.5 operation (usually pins 5&6)? I realize that you have a raid array, and you tried using the drive to rebuild the raid 1 array but it failed. However did you try to disconnect the Maxtor HDD's and leave the WD as the only SATA drive in the system, and then install XP on it?
 

Seekermeister

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No, I have not attempted to install anything with the WDC drive alone. Wouldn't that cause a problem with it matching data with the old drive? I never messed with any jumpers, because I had been told that it wasn't necessary with SATAs. While there is jumper pins as usual, there is no jumper on the drive.

EDIT: I just checked, and the old Maxtors don't have any jumpers either.
 

John

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What is the exact model # of the WD hard drive?
 

John

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Jumper Settings Guide

1) Put a jumper on pins 5 & 6 to force SATA 1.5
2) Disconnect the maxtor drives
3) Hook WD800JD to SATA port 1 on the motherboard
4) Go into the BIOS to see if the WD drive is detected. If it is then the OS should see it.
5) Disconnect the Maxtor w/ the smart error and hook up the WD in its place. Boot into the raid bios and rebuild the array.
 

Rubycon

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Originally posted by: John
Here we go again with the minimum wage workers giving out incorrect information. :p You can use different speeds/brand/size for raid arrays but you are limited to the performance and capacity of the smallest drive.

Format was not the problem with your WD drive. If you can't boot with the drive connected it is a hardware issue. You have to be able to let the bios see the drive before you can partition and format it (unless of course it has already been done on another system). Did you try jumpering the WD for SATA 1.5 operation (usually pins 5&6)? I realize that you have a raid array, and you tried using the drive to rebuild the raid 1 array but it failed. However did you try to disconnect the Maxtor HDD's and leave the WD as the only SATA drive in the system, and then install XP on it?

John, it's agreed that when using non ANSI HBA hardware the drive firmwares should be identical to avoid issues particularly with the striped pairs often chosen by the enthusiast. ;)
 

Seekermeister

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John,

I guess that I will have to make another trip to a store, because I don't have any jumpers to install.
 

Rubycon

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Originally posted by: Seekermeister
MS Dawn,

Would that also apply to raid 1?

Quite possibly but it really depends on the hardware and firmware programming. Unfortunately this takes exhaustive resources to test and analyze the results. If this is for a personal PC and it simply doesn't work then no real loss I suppose.

But if something goes amiss and your data slowly gets eroded over time it can be a big hassle!
 

Seekermeister

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MS Dawn,

I agree that would be a hassle for the data to be corrupted, and that is enough reason to look for another solution. But just for information, would that mismatch account for the drives not appearing in the bios, not booting or offering to rebuild the array?
 

John

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MS Dawn, if that was the answer initially given by the CSR it would have been more than acceptable. As you pointed out matched drives are preferred, but you can use mismatched drives and the array will still function. Let's say your 7 year old array had a drive failure. What are the chances (for the average user) of finding an identical drive? :p
 

Rubycon

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Originally posted by: John
MS Dawn, if that was the answer initially given by the CSR it would have been more than acceptable. As you pointed out matched drives are preferred, but you can use mismatched drives and the array will still function. Let's say your 7 year old array had a drive failure. What are the chances (for the average user) of finding an identical drive? :p

Take the good one and ghost it and ghost back to a fresh mirror of 7200.10's? :p
 

John

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Raid 1 is all about redundancy and uptime, but it doesn't give you an excuse not perform regular data backups on DVD, a spare HDD, a network drive, etc.

Some people will disconnect one of the mirrored drives on a regular basis and allow the mirror to build on a third drive. If at any point a mirrored drive fails, there is no down time, as the data still exists in full on a backup drive.

 

John

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MS Dawn, are you single? I really enjoy a "geekbabe" speaking in techie tongue to me. :p
 

Seekermeister

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Originally posted by: MS Dawn
Originally posted by: John
MS Dawn, if that was the answer initially given by the CSR it would have been more than acceptable. As you pointed out matched drives are preferred, but you can use mismatched drives and the array will still function. Let's say your 7 year old array had a drive failure. What are the chances (for the average user) of finding an identical drive? :p

Take the good one and ghost it and ghost back to a fresh mirror of 7200.10's? :p


The only problem with that idea, is that it would require buying two new drives, and also a copy of Ghost, which I don't have...well, I do have a copy of Ghost, but it is so old that I doubt that it would work. Costs being as they are, I would have to look for a cheaper solution.
 

John

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Originally posted by: Seekermeister
The only problem with that idea, is that it would require buying two new drives, and also a copy of Ghost, which I don't have...well, I do have a copy of Ghost, but it is so old that I doubt that it would work. Costs being as they are, I would have to look for a cheaper solution.

Exactly, and hence my numbered post @ 5:05PM :)

 

Rubycon

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Aug 10, 2005
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Originally posted by: Seekermeister
MS Dawn,

I agree that would be a hassle for the data to be corrupted, and that is enough reason to look for another solution. But just for information, would that mismatch account for the drives not appearing in the bios, not booting or offering to rebuild the array?

Yes in most cases it will work and if you build a mirror with two different sized drives the extra capacity of the one drive is discarded.

There's no patrol reading function on onboard HBA that I'm aware of that could possibly identify a problem with data integrity. Some add on HBA do it in software and most scsi HBA will do it in hardware if the user desires to turn it on.

John: 42 and single. :Q