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Virtual Disk issue, RAID 5, 6 disk array, Perc 6i controller in Dell R610. Foreign flag error.

Help

Hey everybody,

Recently I was checking on my systems and noticed I had a flashing yellow on one drive and then a flashing green/yellow on another drive. I did all the normal troubleshooting and after checking the connections and re-seating the flashing yellow drive, it came back on line with no error. The flashing green/yellow is still having issues. I wanted to back up everything, replace both disks and rebuild the virtual disk, but when in the BIOS, both disks show up with a "Foreign" flag in physical disk management and I can't get the VD back on line. Is there a way to clear the flags to bring the VD back online so I can backup?

I've also checked Google, but most of solutions don't seem applicable in my situation.

The data is primarily a bunch of videos I've taken over the years so I'd prefer to save it all if I can.

Thanks in advance everyone.

Posted Aug 12, 2018, 6:53 PM UTC

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[deleted]•

[deleted]

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FearFactory2904•

Your current config is a failed raid 5. Whichever drive failed or got reseated first, pull it and set it aside. Whichever failed second, leave it in and import foreign config. If you clear foreign config you are clearing your recovery opportunity and accepting the current config of the other drives which is a failed raid 5.

Once you are back online, backup the data asap before the drive fails again. Your window of opportunity depends on how bad of shape the drive is in.

Also if you already cleared the foreign you can technically 'retag' the raid but it involves more work.

2
studiox_swe•

Is there a way to repair a drive in bios? Not really. If one drive would have failed you could rebuild you VD with a new drive, raid5 will not survive two broken drives. I would try to repair the drives with raid5 repair tools, you will not be able to do this with your perc controller I think

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Netwerkz101Yes damnit...still a work in progress!•

Probably a lost cause ...but ...

If you are going to nuke the whole thing anyway (not use a data recovery service),

I'd try to import the foreign config inside the RAID config utility.

I'd actually try first without the failed drive in ... leaving just the drive that was alternating green/amber.

Long shot ....!

1
s13ecre13t•

I am not familiar with hardware raids as I hate them with passion.

Saying this, you can recover the data with a bit of sleuthing. Steps are:

  1. take each drive and create images of them. You need to do this where you have passthrough / raw access to the device (you read all the data blocks, including the hardware raid reserved metadata blocks)

  2. figure out these hardware raid metadata blocks... checkout tool like dmraid that lets you process these

https://linux.die.net/man/8/dmraid

  1. after processing the metablocks you will know raid structure, read up also how the controller does things.

Once you have this information (like seek, chunks, stripes, offsets, layout algo ie: https://www.accs.com/p_and_p/RAID/LinuxRAID.html )

Once you have it all, you can attempt to just create software raid with mdadm assemble and utilize all the params, offsets, chunks, etc.

http://man7.org/linux/man-pages/man4/md.4.html

If this is hard or doesn't yield obvious results you can go further down the rabbit hole and do things mentioned in this post:

http://lists.us.dell.com/pipermail/linux-poweredge/2010-May/042208.html

Which also include python scripts to help figure out hardware raid config.

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