Enhancements in the long-awaited Win2K
Over the years, users have questioned Microsoft's direction in developing Windows NT's file systems and disk management features. I've heard users ask why NT maintains such a large file cache for so few files and why they can't extend partitions using the OS. They also want to know where NT's defragmentation utility is and when NTFS will offer data encryption. Finally, users ask implementation-oriented questions about why you must use NTFS to take advantage of NT's important security features and what the differences are between FAT, Virtual FAT (VFAT), and FAT32.
After much anticipation, Microsoft might finally release Windows 2000 (Win2K--formerly NT 5.0) next year. When the new OS comes out, you can bet it'll be a hot commodity. Everybody wants to get his or her hands on the new Microsoft Management Console (MMC), Active Directory (AD) Services, and Plug and Play (PNP), among other things.
Aside from these new features, you'll want to know what Microsoft has in store for the overall I/O and file system structure. Let's take a look at the new OS to determine whether these changes are technical, or merely semantics.
Changes to Read-Write File Systems
FAT32 is the first significant change to NT's file system since Microsoft redesigned FAT to support partition sizes greater than 32MB. Microsoft first introduced FAT32 in the OSR2 version of Windows 95.
One of FAT32's most important features is that it breaks the 2GB partition barrier and supports drives up to 2TB (2048GB). Although this support is useful to administrators who want to create one large partition for large (i.e., several gigabyte) drives, it is not useful in unattended installations unless the clients are running Win95 OSR2 or Windows 98. In the traditional NT 4.0 installation instances, you must create and format the target partitions before you perform the unattended installations. You typically create the partitions using the DOS command FDISK and use the DOS FORMAT command to format the partition using the FAT file system, which doesn't let you go beyond 2GB when you format the drive from DOS. Supporting FAT32 may be beneficial to NT partitions that you create from scratch during an interactive installation of NT or after you've installed Win95 OSR2 or Win98. Microsoft might adjust installation in the final release to accommodate FAT32 for unattended installations. Alternatively, if you can't get an unattended installation to do your bidding, you can always use disk image cloning software such as Ghost Software's GHOST (http://www.ghostsoft.com) or PowerQuest's Drive Image software (http://www.powerquest.com). Don't confuse FAT32 with VFAT. VFAT is not a file system but an enhanced file system driver for use with NT and Win95. It functions as an overlay to the 16-bit FAT file system commonly found in DOS. If you plan to dual-boot NT 4.0 with any current beta release of Win2K, you can obtain a read-only FAT32 driver for NT 4.0 from Systems Internals (http://www.sysinternals.com).
Another important FAT32 feature that NTFS already implements is that it uses smaller allocation unit sizes and a smaller cluster size than FAT. This configuration results in 15 percent more efficient use of disk space. Slack space occurs when an allocation unit has part of a file or a whole file that doesn't take up the full allocation unit and the remaining portion isn't available for storage. Some OSs, such as NetWare, work around this slack-space problem through block suballocation.
FAT32 provides more file system stability than FAT. Microsoft expanded the boot record on FAT32 drives to include a backup of critical data structures. FAT32 can also maintain multiple copies of its File Allocation Table. In the event that the first table is corrupt or unavailable, FAT32 relocates the root directory and uses a backup copy of the File Allocation Table. FAT32 doesn't restrict the number of entries that can appear in the root directory. However, 16-bit FAT limited the root directory to containing 512 entries of directories and files. This limitation led to Out of disk space errors when a user attempted to copy a file to the root directory, even if the directory had 800MB of disk space available.
Legacy compatibility will be the biggest concern with FAT32. Microsoft said certain APIs might not work with FAT32; therefore, vendors have to modify common programs such as Scandisk, Defrag, and fdisk. Vendors also have modified third-party products such as Partition Magic to support FAT32. In addition, hardware vendors will have to update certain file and filter device drivers (such as those used by virus scanners, and Microsoft will update its file system drivers to support FAT32. In beta testing Win2K, many users reported volume corruption on boot and system volumes formatted using FAT32 and configured to dual-boot Win2K with Win98. At press time, no workaround was available. You should never install a beta on a production system.