I wiped out my MorphOS installation on my PowerBook by accident and overwrote the entire SSD with a Linux installation. :(

Can someone please help me recover some files that I don't have backups of?

My system partition was SFS and my data was on a PFS3 partition.

I'm not too bothered about the system partition and SFSDoctor was no help at all, but I really need to recover some files from the PFS partition and PFSDoctor was even less helpful.

Is there any chance I can get back these files or are they lost for good?

Please give more details about what you did. What was the partition layout before, what is the partition layout now and where did you install Linux to?

You can only recover data which has not been overwritten. If you deleted the existing partitions and installed Linux in the same place, then everything is lost. Only if the area on the harddrive where the PFS partitions was has not been touched, there is a chance to recover something.

Especially the beginning of the partition has to be untouched because PFS concentrates all meta data at the first part of the partition.

Hi Thomas,

Before this the layout was

1MB Newworld boot partition
512MB HFS partition for boot.img
2GB SFS partition for System:
40GB PFS3 partition for Work:
15GB EXT4 partition for /
1.5GB Linux swap partition

I ran the Ubuntu installer from the live cd and told it to format the existing ext4 partition. The installer segfaulted so I ran it again and chose the option to reinstall over existing installation, but it didn't do what I assumed it would do and instead it wiped the entire partition map and created:

1MB Newworld boot partition
57MB EXT4 /
2.5GB Swap partition

The new ext4 partition has 3.16GB of data installed to it so I guess it has overwritten the PFS metadata at the beginning of the old partition. :(

I'm open to all suggestions that might help me recover my sourcecode though.

You can try to recreate the exact same partition map. With every partition located at the exact same position as the old ones. Byte for byte. Easier said than done...
Then run sfsdoctor and pfsdoctor over them.

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Unfortunately I can't remember the exact layout, there were a few zero or almost zero byte empty partitions between a few of them for some unknown reason.

I'll have a go though and see what happens, I'll dd the entire disk and try searching for certain strings with a hex editor as well.

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Yes, that's bad.

PFS reserves a certain percentage in the beginning of a partition for its directory and begins behind that with storing data.

So if the PFS and the EXT4 partition start at about the same place, it's rather unlikely that something can still be found if the PFS partition was not filled with at least 3 GB of data and the files you are looking for are young enough to be stored later than the first 3 GB of the partition.

Given that the directory has been overwritten completely, searching for strings in the disk dump is probably your only option. Be prepared that you really only find file contents or fragments of file contents. All meta data was stored in the directory area. There is no information in the data area about which file a piece of data belonged to or where another fragment of a fragmented file could be located or in which order fragments were stored. You won't even find file names.



[ Edited by Thomas 19.12.2013 - 13:43 ]

There was at least 10GB of data on the PFS partition so I'm hoping the files I need are after the 3GB of ext4 data and are in one consecutive block of bytes.

I took a backup last week but I made quite a lot of changes in the last couple of days and I really don't want to recreate those changes from my memory unless I really have to. :/

I think I'm going to work on remote copies from now on.

Is there an sshfs for filesysbox yet? I volunteer to be a beta tester if testers are needed.

Spent the last few days trying to recover stuff and managed to rescue a big fat zero, so will have to manage with my backup from a week ago.

Ah well, we live and learn. :/

[ Edited by Intuition 22.12.2013 - 17:33 ]

Just for the record:
diskvalid (not included in MorphOS) may give better/other results than PFSDoctor...

@polluks

No, DiskValid can't help any better than PFSDoctor when nearly third of the data is overwritten.

At least PFSDoctor asserts my partition is fine.
But DiskValid says
Code:

I'm not certain it's a positive sign that the tool finds errors the other one doesn't.

Either way, no tool (diskvalid or pfsdoctor) can recovered data that has been overwritten. Frequent backups are the only remedy against this.

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Depending on if this bug is critical...
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sure

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You are lucky (and smart) you have a backup from just a week ago. On Amiga I deleted a partition trying Linux APUS in 2002, and never got anything back. Tons of mods and PD stuff, hundreds of demos that came with my HDD, thousands of hours getting my desktop to exactly how I liked with icons and app setups, AmigaZeux IRC logs, pictures, documents... I never managed to find most of the lost files again, and never bothered configuring AmigaOS again.

Did exactly the same on MorphOS years later, and once again I never quite ever had the heart to restore everying I'd lost. I just left it in an unconfigured mess to present day.

Backup backup backup backup...

[ Edited by KennyR 18.11.2020 - 21:58 ]