HDD Recovery - HFS->EXT3
 

Hi guys, I think this is the most appropriate forum as I am asking if software is available to fix a hardware error.

here goes.

basically, I am running diskwarrior on my mac now to try and fix invalid b-tree node size error. It is my boot drive and therefore cannot get onto the operating system. I have used live linux distros to try and get at the hdd that way, I have installed HFStools and testdisk and tried almost everything possible from within Linux itself to recover this HFS+ drive, but they were all a no go

my last resort was to try diskwarrior and it is rebuilding the drive now, well it has been for about 38 hours now but doesnt give any indication as to how long it will take, I am pretty sure I am right in thinking data is never truly deleted until it is overwritten, is that right? even if reformatted, would I be correct in thinking that if I were to format the drive and install linux on my machine, some of the data on the Drive would still be technically recoverable, even though the file system has changed? ie from HFS to EXT3

If this is technically possible what software would I need to try and recover files from a drive that has been formatted from HFS+ to EXT3?

It doesn't matter if I cant get it all, or might be more hassle than its worth, my girlfriend has another laptop to use for now and is in no hurry and I like getting to play around with Linux. The data is somewhat important but not enough so to go through the whole sending off the drive and paying hefty fees, it would be very nice to get back and I enjoy working in linux and learning more about software/hardware etc.

Thanks guys

Software doesn't "fix" hardware errors. At most it can work around things, for instance like telling 'badblocks' to mark and skip bad blocks or telling 'dd_rescue' to read a disk back-to-front and skip errors AFAIK.


The first thing you should have done is make a bit-by-bit backup copy to file of the whole disk. Insurance, basically.


Saying "no go" doesn't reveal anything technical, nor any problems with GNU/Linux HFS(+?)-capable tools or maybe the initial hardware problem you've talked about prohibiting proper access. Details welcome. Please elaborate. (Next to that while HFS(+) specs maye be widely available it still is a proprietary file system, meaning support for enhancing HFS(+?)-capable tools heavily relies on available development sources, if any).


That depends on what caused the errors, how long something was deleted, if freed blocks were re-used, if it's a journalling file system et cetera.


Simply said "formatting" overlays a disk area with a mesh-like structure, so yes, in the "gaps" data still resides. However file system entities are no longer tied to the structure so a recovery tool is left without paths to walk to find items easily. That's where header slash footer carvers like Photorec come in. However given that only a limited set of headers and footers is available, that a file system entity may use direct and indirect links for storing pointers to actual data, that SW can be thrown off by HW errors, plus the other problems mentioned before does mean you should not get your hopes up too high.