Corrupted File System

Overview

File system is the term assigned to the logical entities and software practices to check the access to the data stored in the storage medium. In other words, file system can be designated as a manager of your hard drive. Different operating systems have compatibility with different file systems. Some operating systems have their own proprietary file system. The file system consists of several components such as- partition table, Master File Table (MFT), File Allocation Table (FAT), a boot sector etc. Among these MFT and FAT are the most significant components as these tables keep the records of all the files and their fragments. A file system is said to be corrupt if it when they become unreadable or overwritten. The corrupted file becomes inaccessible forever.

Some Significant File Systems

Let us have an insight into some of the popular operating systems with their linked file systems:

• (MS-DOS, PC-DOS) - Data Operating System prevalently known as DOS is the earliest operating systems available. The basic requirement of DOS is FAT file system. Only specific versions of FAT file systems are compatible with corresponding DOS, e.g. FAT12 for DOS1.x and DOS2.x or FAT16 for DOS3.x.
• Windows- Versions of this Operating system was compatible with FAT12, FAT16 and VFAT. VFAT was further modified to FAT32 to enhance the storage capacity and performance of the operating system. FAT is generally available in three forms namely FAT12, FAT16 and FAT32, where the numbers symbolizes the number of bits used to enter the information in clusters

Structure of a FAT 16 volume




Macintosh File System(MFS) is the proprietary file system used by systems designed by Apple computers. It is a flat file system with no support for hierarchical directory structure

Fixing the Corrupted File System

Major file system damages are attributed to perturbations in the i-node or in the directory structure of superblock information. This may be caused by certain disorder in hardware or an already corrupted program which get accessed to i-node or information superblock. Following are few suggestions which are fruitful in fixing the damaged file system:

• Fast SMIT paths may be used to unmount the corrupted system; smit unmountfs (for a file in fixed drive) and smit unmntdsk (for a file in removeable disc)
• The file distortion due to corrupted file system may be assessed by giving fcsk command. The fcsk command diagnoses and subsequently repairs the damage. This command usually conservative and avoid all those actions that may result in data loss. It recommends a complete destruction of file system in specific cases.
• If the error can’t be sorted out then restore the file from back up
• Last but not the least in case you are experiencing difficulty in restoring the files, it is always advisable to seek professional help.

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