Recover ext3 partition overwritten by GPT

How to use TestDisk to recover lost partition
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Posts: 2
Joined: 15 Dec 2013, 11:51

Recover ext3 partition overwritten by GPT

#1 Post by thedriver »

I have a XenServer ext3 partition on a 6TB iSCSI target. On it where my virtual disks.
Unfortunately, a Windows PC connected to the same iSCSI target and the disk was initialised using the GUID Partition Table (GPT). :evil:
Fortunately, it wasn't formatted with any file system though.

I am currently analysing the iSCSI target from a Windows PC using TestDisk. The scan is currently only at 17% but it is already showing 11 partitions with various sizes. Every partition shows "MS Data" as the type though.

I'm not sure how I will recover these to a single ext3 partition. Help appreciated :!:

Posts: 2
Joined: 15 Dec 2013, 11:51

Re: Recover ext3 partition overwritten by GPT

#2 Post by thedriver »

So TestDisk has been running for over 7 hours and is only 18% through (it is still ticking over at the same pace as when it first started).

It hasn't found any further partitions yet. Given that the iSCSI target was thin provisioned and only using about 1.5TB of 6TB can I safely stop it now and try to restore these "MS Data" partitions to their original single ext3 partition state?
Or do I need to wait it out until it finishes?

I only have about 2 hours left before I need the data of the partition and at the rate that TestDisk is running, it is going to take 500 hours (just over 20 days) to finish anaylising the disk. I really don't have that long!

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Re: Recover ext3 partition overwritten by GPT

#3 Post by cgrenier »

My answer is probably too late but yes if TestDisk has found your partition, you can choose stop, rewrite the partition table. In Advanced, select the Linux partition and choose Superblock. You may have to use given fsck command to repair the filesystem.