|Information about File Systems (Old)|
- PGP Keys
- Vossen's Law
- Firewall Rules
- Home Net Security
- Snort Books
- Sec Tools
- Honeypot Stats
- Firewall Stats
- IP Calcs
- SME Server
- Backup (DI-30)
- Win Tools
- Win. Shell Scripting
- POSIX Redirection
See The Filesystems HOWTO/FAQ for far more detail about many more filesystems than are listed here.
Download a more in-depth version of this document in Word 6/95 format.
PC File Systems
Cluster Size and FAT16
Drive Size FAT Type Sectors Cluster (logical volume) Per Cluster Size ---------------- -------- ----------- ------- (Floppy Disks) 360K 12-bit 2 1K 720K 12-bit 2 1K 1.2 MB 12-bit 1 512 bytes 1.44 MB 12-bit 1 512 bytes 2.88 MB 12-bit 2 1K (Hard Disks) 0 MB - 15 MB 12-bit 8 4K 16 MB - 127 MB 16-bit 4 2K 128 MB - 255 MB 16-bit 8 4K 256 MB - 511 MB 16-bit 16 8K 512 MB - 1023 MB 16-bit 32 16K 1024 MB - 2048 MB 16-bit 64 32K
This means that with a 2 gig partition, a file that is 512 bytes in size takes up 32K of hard drive space. The resulting 31.5k is called "slack space" and is wasted!
Issues with OSR2/FAT32
Editorializing by JP
[...] There are significant incompatibility issues between FAT16 and FAT32. In that respect, use of FAT32 may be compared to use of NTFS. Specifically, most disk utility (Norton) and backup programs will not work. Virus programs, un-installers games and disk compression tools, among others, may also be affected. Users may be better off sticking to the 2gig partition limit and living with slack space.
Windows 98 is also supposed to come with a Fat to FAT32 converter (similar to the NT FAT to NTFS convert.exe) that will do one-way, on-the-fly conversions of FAT to FAT32. And NT 5.0 may support FAT32 volumes, as well as NTFS and FAT.
In order to maintain the greatest compatibility possible with existing programs, networks, and device drivers, FAT32 was implemented with as little change as possible to Windows 95's existing architecture, internal data structures, Application Programming Interfaces (APIs), and on-disk format. However, because 4 bytes are now required to store cluster values, many internal and on-disk data structures and published APIs have been revised or expanded. In some cases, existing APIs will not work on FAT32 drives. Most programs will be unaffected by these changes. Existing tools and drivers should continue to work on FAT32 drives. However, MS-DOS block device drivers (for example, ASPIDISK.SYS) and disk tools will need to be revised to support FAT32 drives.
All of Microsoft's bundled disk tools (Format, FDISK, Defrag, and MS-DOS- based and Windows-based ScanDisk) have been revised to work with FAT32. In addition, Microsoft is working with leading device driver and disk tool vendors to support them in revising their products to support FAT32.
NOTE: A FAT32 volume cannot be compressed using Microsoft DriveSpace or DriveSpace 3.
Microsoft will support the functionality of the FAT32 file system for error- free reading, and saving of files either in real mode or protect mode. We support the real- and protected-mode tools included with Windows 95. Microsoft will not provide support for programs that will not run on the FAT32 file system. For legacy programs that will not install on a FAT32 volume, or will not properly save files or read them, you will have to contact the manufacturer of the software package.
NOTE: Cluster sizes of less than 4K on FAT32 volumes are not supported by Microsoft.
Other Interesting File Systems
Last Modified: $Date: 2007-11-28 02:26:46 -0500 (Wed, 28 Nov 2007) $