Hi Camaleón, > > But that is extremly dangerous...: you risk to loose/destroy > > informations on the damaged filesystem (nobody guarantees, that scandisk > > is not destroying data...). And especially defrag: this WILL destroy > > data, which are in lost files (=sectors of the harddisk which seem to be > > free according to the file system...). > > (...) > > I've never heard neither seen that before and have worked with ntfs > volumes during many years. In fact, I've managed to "restore to live" > windows systems that were unable to boot up by following that procedure > (even an unexpected shutdown can make the OS to be unbootable -system > files tend to become easily corrupted- and checking the file system > structure solves the issue). > > Scan disk (chkdsk) and defrag are the standard and recommended tools for > dealing with MS file systems problems. Maybe they cannot solve the > problem but won't aggravate it either. And before "wiping out" the hard > disk, I think it is at least worth a try. The point I wanted to make is the following: Defrag shifts parts of the files -- and in order to do so, it OVERWRITES unused parts of the disk. Now: as soon as the filesystem is corrupted, one can't trust anymore in the information which parts are "unused" -- so it can happen that defrag (or any other tool which writs on the disk) overwrites file-informations, which belong to a "lost" file, but which are believed to be "free" and "unused" by the filesystem. In my opinion, this danger is not limited to ntfs, but exists in every filesystem: as soon as the filesystem is corrupted, one can't guarantee that the blocks marked as "free" don't contain usefull information -- and that's why I wouldn't write anything on the partition!
A similiar point is true for scandisk / chkdsk: Again, independent on the filesystem: Once the filesystem is corrupted, the recovery tool has to make assumptions about what is the "correct" information -- and if it makes the wrong assumption, it WILL destroy data. For example: How can chkdsk guarantee that, whenever it writes some information on the disk, it uses a truely "free" part of the disc? maybe on this place was a piece of an important file, which was lost by the file-system corruption? Of course the question is, how important the data are -- is it worth the effort to first create a copy of the partition and then to work on the copy? Axel -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20101128174818.ge5...@axel
