Filesystem Seems Damaged...How?

Using TestDisk to repair the filesystem
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Re: Filesystem Seems Damaged...How?

#11 Post by nishankyadav »

I am getting this on D drive which is data partition

cannot open file system File system seems damaged
laptop is booting and fine on c drive but d drive files are not accessible

kindly help
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Re: Filesystem Seems Damaged...How?

#12 Post by cgrenier »

Try TestDisk, Advanced, select the partition, Boot, RebuildBS, List. If you can see your files, choose Write and confirm, Quit
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Re: Filesystem Seems Damaged...How?

#13 Post by frevab »

I got the advise from an article on another website to access the drive using Linux instead of Windows as the damaged filesystem is a Windows thing. ... ecame-raw/
I am not familiar with Linux but could boot up using the PartedMagic cd and access all files on the HDD without any problems.
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Re: Filesystem Seems Damaged...How?

#14 Post by oldefoxx »

A drive thatis reported as being damaged does not mean it is physically damage, though that can happen, especially if it is mechanical an mobile. What the damage is is normally an inconsistency in information about the drive, as different recirds are kept of the number of sectors, their type, their size, where they start, where they end, and within each partition where the folders and files are physically stored, how they relate to each other, and so on. On top of which more advanced methods keep journals of changes in the works, so that if they get disrupted. then journal can be resumed to bring them up to date. <not sa simple as you thought, right?

From what I understand, when certain types of disjoints in the records take place, most accessing software gets stumpt as to how to proceed. Sometime the better thing is to do nothing rather than chance makinf things worse. Then you need something like fdisk or debugfs to help. But if you don;t know enough, you can't really manage debugfs. There are instructionsd online for finding what debugfs needs to work. But it can be stumped because it wants to go high level down, When the high level is absent, that's it.

Testdisk goes bottom level up. It skips the tables and goes right to the data in the sectors or clusters, I'm winging it here, because I really don't know the workings of testdisk. But I understand disk structures as a concept and how disk forensics would work. The actual data does not lie. Especially if you know what type format was used when the partition was set up. The most important data to recover is usually text data and image files. Both tend to fit certain patterns. Image files have identifiers and structure. So does some data or text file. If I look at a short string of codes that can translate into the ASCII code and form the letters " brick wall." that is likely a part of a text file.

I don't have to look specifically for "brick" and "wall separated by a space. I can do code generalizations and look for patterns in a mask. replace printable symbols with a single symbol in a mask and see the results. if all the characters above were replaced by "x", <i would see "xxxxxxxxxxxx" The more consecutive "x"'s. the more likely it is text. The more groups of "x"s the greater the likelyhood it is text. If you see LF codes between text groups, it is likely a Linux or Mac text file. If you find the codes for CTLF pairs, then it is a DOS/Windows document of some sort. Keep extending the rules based on known conventions, and you can correctly identify a large selection of commonly used file types. some help with file extensions, but actually the paths, names, and extensions are not stored as part of the file. They are part of the higher level structure that is only chained to the actual file by a pointer to its start. These too can be recovered.

When you delete a file. the name and pointer are discarded but the data in the file remains. As the contents of the disk change, that data will gradually be written over by new files and their contents. So to get your original files back, it is important not to be adding new files or copying back recovered files as this could overwrite portions of existing files yet to be recovered. Files are not stored in sectors or clusters consecutively. They are scattered like the pieces of a puzzle or agame where you find one clue that points you to the next clue. About the same idea that all kids in one class do not have to live next door to each other. When rhat class is out, they recluster with other students for their next class. The classes and the rooms assigned are at the discretion of the administration. The teacher assigned is like a folder that keeps the class together as a group. That makes the students like files, and each one can be different.

It's possible to reconstruct a partition on the fly, but very difficult and time consuming. First you have to dispense with the admin services yet use its records to find empty classrooms to formulate new classes in, freeing up the classrooms one by one. You have to make sure the classroom is ready for reuse, no repairs are required, then take another class that would fill it best and move it here next, There is software that does this for normal drives and they are called defragmenters. They require a lot of time to do this, especially with large drives and lots of files,. And they show little in the way of performance improvements. Their gains immediately begin to fade as files are removed and others added, and fragmentation begins to happen again.

Only electronic devices like solid state drives (SSDs) have the randomness needed to act as though they are defragmented all the time. Devices connected by USB ports, to the Internet, or by something like WiFi are much slower than internal drives because the latter use shorter distances and a simpler, faster protocol for communicating with the PC. If you want more computing speed, the three main steps, in order, are: (1) More RAM, (2) a bigger, faster hardrive or a second drive, or (3) a newer, faster, more powerful computer. Many go right to (3), but it is by far the most expensive solution.
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Re: Filesystem Seems Damaged...How?

#15 Post by likekinds »

Thank you for your very impressive reply. It's too bad that my ability to absorb and comprehend it is quite limited.

It seems to me, the way data is stored, retrieved and rearranged on a hard drive platter is illogical and unnecessarily complicated. I guess not, though. It works...and for the most part, works very well.