Author Topic: LS441D - Possible to recover my RAID 5 with 3 drives failing?  (Read 130 times)

ivan.wong

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LS441D - Possible to recover my RAID 5 with 3 drives failing?
« on: December 02, 2017, 10:28:24 am »
Any expert here? Couple of days out of sudden disk 2/3/4 are failing at the same time. Could it be some else and not the disks? Now I have only disk 1 running oh gosh...

Tried recover disk but unsuccessful. My Array 1 status fail. Any good advice will be greatly appreciated!

Thanks!

Eastmarch

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Re: LS441D - Possible to recover my RAID 5 with 3 drives failing?
« Reply #1 on: December 04, 2017, 10:08:03 am »
It is theoretically possible for a badly failed drive to make other drives incorrectly show failed. Try booting with drives 1/3/4, 1/2/4 and 1/2/3. If no joy, then you'll need to restore from backup.

You'll need to identify SMART statistics for those drives too. If you can connect them to a windows machine, CrystalDisk Info will give you a SMART readout.
**A single copy of data, even on a RAID array, is NOT a backup! Hard drive failure is not a question of IF, but WHEN! Don't take my word for it, take Google's!**

ivan.wong

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Re: LS441D - Possible to recover my RAID 5 with 3 drives failing?
« Reply #2 on: December 05, 2017, 10:03:51 am »
Thanks for the good advice Eastmarch! Found out that my drive 2 having bad sector that not even a test run with the WD DLGDIAG is able to execute it. Tested my drive 3/4 & I got a pass status. I guess the drive 2 is badly corrupted or I have to replace it with a new HDD. I tried using diskpart clean to erase all data from drive 2 but Windows gives me a cyclic redundancy check error.

The question is, if I replace a new HDD for drive 2, can I recover my data with drive 1/3/4 attached back to my NAS?

Texturtle

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Re: LS441D - Possible to recover my RAID 5 with 3 drives failing?
« Reply #3 on: December 05, 2017, 11:41:25 am »
Will the unit boot with drives 1, 3, and 4 in now? If so then you should be able to replace it and rebuild the RAID.

ivan.wong

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Re: LS441D - Possible to recover my RAID 5 with 3 drives failing?
« Reply #4 on: December 06, 2017, 06:55:57 am »
Have not tried yet, the new hdd still in erase mode. gotta give it a try once it is done erasing.

ivan.wong

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Re: LS441D - Possible to recover my RAID 5 with 3 drives failing?
« Reply #5 on: December 08, 2017, 05:09:14 am »
Just to update my test here. Replaced with a new hdd for Disk 2 & use Diskpart Clean all to erase the disk. Insert back new hdd to drive 2, at first drive 3/4 showing fail status. Execute Rebuild Array 1 with Disk 1 & Disk 2 selected (I don't know why I can't select drive 3/4 as well). Rebuilding Array successful and I can see back my previous data. But I have another problem now, the disk 3/4 remained Unformatted but Array 1 status is Normal.





What seems to be wrong here?