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jcbcompu1Flag for United States of America

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Raid 5

I have a Dell Server PowerEdge 2800 with 3 hard drives, Raid 5, two of them failed, showed in the Raid Configuration Page, only 1 is healthy. Can I rebuild if I get two new hard drives.
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Michele Segato
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Unfortunately you can't.
With 3 disks you can only have 1 broken disk to recover
Hi

RAID 5 configuration allows for one drive failure, so in answer to your question no.

Before any steps are taken I'm guessing you have a backup of the data? Please say yes....
You could try forcing the drives back online, I've had servers in the past that the disk has just dropped off. If you do force the drives back online you do face the issue of corrupting the entire RAID (but yours is broken anyway).

Otherwise if you need the data then seek advice from a data recovery company.

Jawa29
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Well the situation is like this. I got this server from a customer, apparently the old IT left with no trace, so I have to work with what I have. Now , should I try to get the 2 new drives or your saying to try to put them back online with the existing two drives, by the way, all thee drives have a green light in front of them.

Thanks

To better explain , when you have N disks in raid 5 , the data is split among N-1 disks and one disk is used to  calculate a "bit parity" with the other disks. If you break one disk, you can rebuild the data using the parity disk.

But if you break 2 disks, there are no chances
You could try to  put the broken disks back online and cross your fingers. The RAID is already broken so if putting them on line fails, you can't do further damage: the data is already lost
Have you tried to re-seat the drives already? You may get lucky and one of the 2 currently bad appearing drives is still ok and you could get back to the data.
I agree force the drives back online through the RAID cards utilities and cross your fingers... If you have no backup you have no data full stop, you could perform a miracle when you force the drives back online and everyone will love you or it doesn't work and they slag the old IT off for the rest of their lives :) it's a win win for you and at least you'd be willing to have a go.

Jawa29
Ok great suggestions, as a matteer of fact, i tapped the 2 bad drives and the light came on. Let me try
First try forcing only 1 on at a time, forcing both back online if they failed and different times can corrupt the array bad enough even a data recovery facility wont be able to save it. So force one of the 2 online and see if it boots, if it does try a rebuild on the offline drive. If it doesn't boot force that drive back offline and force the other online and try to boot. However if there is important data they want to recover try this software first http://www.runtime.org/raid.htm (the trail version is free and will let you know what it can recover before you pay for it).
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Member_2_231077

Too late with that advice by the sound of it Jamie :(

With an image of all 3 disks they could probably ensure 2 were in sync but now it may have overwritten an up to date on with an out of sync one.
Probably Andy but I had to try, plus it may help someone in the future with the same issue. But I guess we'll see when the jcpcompu1 posts the results.
Jamietoner, ok so from when i can gathet I will try one good day and one bad drive right , i will phisycally remove the 3rd drive right ?
Sorry, my typing went bad, no day, good drive
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jamietoner
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Jamietoner. Thanks for the clarification. I will try that.
Best to imae them first if there isn't a backup - you'll need a non-RAID controller to mount them on for that. Once overwritten it's gone - unless there's a backup.
Do not try booting the system, make all attempts through the ctrl-M option during boot up to get into the RAID controller while you have new drives handy.

1) add the new drive as a hot spare if not an option, skip this step.
2) force the last drive that was marked as bad online
3) replace the other failed drive with a new one and let the rebuild process complete.
4) once complete, replace the bad drive from step 2 with a new drive

At times the drive gets kicked out while not being dead.  The issue is that the array may have been in a downgraded state for a while when the first drive was kicked out of the array and no one checked on it.
The View Configuration Page shows one Drive Online 2, Fail.
The Rebuild Configuration Page show all Fail.
What it that means
Means restore your backup or if you don't have one then stop now before you make it worse and get an expert in.
We dont have a backup as far as I know. You are the experts so tell me what to do mext
Im wondering if the controller card is good.
Drive 0 is online drive 1 and 2 are offline. The array is failed. Nothing we didn't already know. If possible I would swap these three drive into another system and use raid reconstructor to recover the data. You can try to force the drives online as I explained earlier but there is no guarantee that will work especially since we don't know if a drive(s) are actually bad or in what order they went offline in. Does the customer have a backup of the data? Have you ran diagnostics on the drives?
At this point since data obliviously needs to be recovered and imho it needs to go to a professional data recovery facility. More than likely the controller is fine, it looks like 1 drive failed and the system was ignored until the 2nd drive failed. Your customer is about to find out exactly how expensive not keeping a backup can be.
jamietoner, ok so you are suggesting to try the raid constructor to recover the data. Stupid question.
Do I need another server or can I downloaded on this one. I dont have another server.
Another server with a working os and a non raid scsi adapter would be best.
Can I use a regular windows computer, install the scsi card on it, new scsi drive, load OS and then download the software to check the other drive ?

According to Raid Recontrusctor I just need XP and few others.
Do you know what kind of controller card I will need. I like your idea. THere is a chance.

I have used an adaptec 39320 card in my desktop with 80-pin to 68-pin converters in the past to recover data from a failed array.
So jamietoner what I have to do is get one of this cards and a fresh scsi hard drive, load OS (XP) on it, download the software and then hook up the server drive and run the utility ?
or use a computer with a SATA drive and OS in it, install the SCSI card, drivers and see if I can run the utility on that drive ?
Im no sure if on the same computer I can have a SATA drive (bootable) and a "secondary" drive as scsi drive.
Thanks
Whether or not this works Im going to go this route jamietoner.

During the bootup, can you configure the BMC interface?
You could use use ipmitooll to access the system logs to see which drive was kicked out last. to force it online. Do not try to force one online as a guess as that could destroy the "remaining good" data on the still live drive.

I think within the RAID controller there is access to a log/event that will tell you which drive was kicked out last and this is the drive you need to force online.