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CRC Cyclic redundancy check issue

Posted: 30 Nov 2013, 14:02
by steveng
Hello Everyone,

I am new to here and I found most people is mention to use TestDisk or PhotoRec to recover their corrupted data or corrupted HDD. I hope some expert can please provide advise for step-to-step and hope to recover of my child birth photo and video.

I'm not sure if my situation is really that bad than everyone else, I have list below what I have done til I face data error (cyclic redundancy check) issue

1. I store my data under an on-board intel rapid storage technology and running raid-5 with 5 x 2TB hdd, and total I have 7TB capacity (real data only 1.5TB)
2. I want performance of write using the raid, so I decide to rebuild in a raid-10
3. I use Acronis Backup & Recovery 11.5 to do a full backup (archive1.TIB backup format), the backup went successfully to an external HDD 3TB
4. The real data is only 1.5TB, however I confirm to ensure I can read the backup data, and it showing 7TB as a whole volume in the Acronis.
5. I was believe the backup is good, so I went to delete the raid-5 and rebuild with raid-10 (all data is gone during the rebuild)
6. Once raid-10 is built, I try to recover the backup (archive1.TIB)
7. While the Acronis recover data process up to 43%, my premise have power outage and lost power access for the computer
8. Once power have restore, I try to run the same recover process again, and things go WRONG!!! **Data error CRC**
9. I can't do a simple copy of archive.TIB to another 2TB HDD, I tried xcopy, chkdsk /f, I still got data error CRC
10. I tried clonezilla to do disk-disk, but only 300GB RAW data was copy and it pick up the source as 7TB volume different to the 3TB External HDD
11. I have go through the CRC wiki and get to understand the issue, then I have foung TestDisk may able to fix CRC (http://www.cgsecurity.org/wiki/TestDisk_6.14_Release)

Could I please have some advise how I can fix the CRC on the external HDD using TestDisk so I can then recover the data. The data is very very important to me and I am most concern to recover my two daughter photo (from birth til 3 years old)

I'm here to thank you in advance for who checking this thread
Steven

Re: CRC Cyclic redundancy check issue

Posted: 01 Dec 2013, 18:27
by cgrenier
Is the CRC error on the Acronis file, the disk holding the acronis file or the destination disk ?
If the problem is on the disk, you need to clone the disk to a new empty one as described in
http://www.cgsecurity.org/wiki/Damaged_Hard_Disk

Re: CRC Cyclic redundancy check issue

Posted: 01 Dec 2013, 20:19
by steveng
cgrenier wrote:Is the CRC error on the Acronis file, the disk holding the acronis file or the destination disk ?
If the problem is on the disk, you need to clone the disk to a new empty one as described in
http://www.cgsecurity.org/wiki/Damaged_Hard_Disk
Not too sure whether is CRC error on Acronis or external HDD, but I just can't move the main acronis backup file on the external HDD to any other. Do I need to have a same HDD size or larger than the corrupted External HDD to do imaging?

I have already ran TestDisk to image the external HDD into dd format (54% so far in 2 days), however I will try your method on the link you have provided.

Thanks
Steve

Re: CRC Cyclic redundancy check issue

Posted: 03 Dec 2013, 12:32
by steveng
Thanks cgrenier,

What is the next step after I clone the disk to image in *dd* format.

Do I follow the instruction as start a terminal and run *testdisk image.dd*?

Thanks

Edit: I have done imaging the disk and found heaps of CRC message which I could not understand of the meaning, possible someone please could explain whether it is a sector corrupted or something else?
file_pread(13,1,buffer,20967737(1305/46/15)) ReadFile Data error (cyclic redundancy check)