Filesystems

Windows 2000 systems can support the following file systems: FAT, FAT32 NTFS - New Technology File System CDFS - Compact Disk File System UDF - Universal Disk Format for DVDs. EFS - Encrypting File System runs as a service and is used to encrypt and decrypt files on an NTFS file system for security purposes. The EFS is not a file system like NTFS since it does not create partitions and control the placement of file data, it only is used to control the encryption of data. See the Section called "Security" in this document for more information on NFS. FAT Filesystem Characteristics Used with DOS, it can only support partitions up to 4 G. No spaces are allowed in the file name. FAT32 or VFAT Filesystem Characteristics VFAT - Virtual File Allocation Table introduced by Windows 95 which allows long file names. VFAT is not natively supported by Windows 2000. FAT32 filesystems support partitions up to 32GB. Filenames up to 255 characters long. Filenames begin with a letter and exclude " / \ [ ] : ; | = , ^ * ? The last part is the extension but spaces can be used It supports file attributes used by DOS such as read-only, archive, system, and hidden. Won't support running POSIX applications. FAT partitions provide no local security, only share level security across a network. NTFS Filesystem Characteristics

Windows 2000 NTFS file systems are newer than Windows NT NTFS file systems. In order for Windows NT and Windows 2000 to use the Windows 2000 file system together, the Windows NT system must have service pack 4 or later installed.

• Filenames up to 255 characters long
• Filenames preserve case but are not case sensitive.
• Filenames exclude " / \ < > : | * ?
• Supports built in file compression as a file attribute. Compression is applied to files in a folder if that folder has its compression attribute set. Also optionally sub folders and their contents may be compressed. Compression is not supported if the cluster size is above 4K in size. Moved files retain their compression attribute, but if they are copied they will assume the compression attribute of the target folder.
• Provides automatic transaction tracking of disk activity for correcting corrupt or failed operations.
• Supports auditing.
• Provides sector sparing.
• There is a recycle bin for each user.
• Windows 16 bit and DOS environments can't use this filesystem.
• A master file table is used to save individual file, boot sector, disk structure, and file recovery information.
• Automatically makes 11 character DOS file names. When the first 8 characters of long filenames match, the first four DOS file names use the first for characters of the long name, the ~ and 1, then2, etc. After the fourth duplicate name, the first two characters are used, then the next four characters are hashed, then the ~ character then a number. The first two duplicate file names may be: DOCU~1.DOC and DOCU~2.DOC. The long extension is used as part of the extension for the 8.3 filename alias.Directory entries used by long filenames include 1 for the 8.3 alias and 1 for each 13 characters in the long filename.
• Provides file logging ability and file recovery.
• Supports POSIX.
• Maximum file or partition size of 16 exabytes.
• Supports file sharing with MacIntosh clients.
• The disk is in 8M bands with a 2K file allocation map between each band. The 2K map is a map for the associated 8M band. This structure is called the BTREE and is used to reduce fragmentation.
• Supports file encryption with the Encrypting File System (EFS) on Windows 2000.
• Allows volumes on remote computers or local computers to be mounted as though they are part of the same partition they are mounted on. This feature is available on Windows 2000.
• Disk quotas (tracking of disk space) on a user by user basis are tracked.
• Removable media formatted in NTFS can be changed and accessed without rebooting the system in Windows 2000 (not NT).

If installing DOS with NT, install DOS first so DOS will not corrupt the NT boot sector and stop the NT boot manager from running. Floppies are formatted as FAT, not NTFS.

CDFS

The file system that supports compact disks (CDs) is the Compact Disk File System (CDFS).

UDF

The file system that supports DVDs is the Universal Disk Format (UDF).

Filesystems and Windows Systems

Operating System	NTFS	FAT32	FAT	CDFS	UDF	HPFS
Windows 2000	Yes	Yes	Yes	Yes	Yes	No
Windows NT 4.0	Yes	No	Yes	Yes	Yes	No
Windows NT 3.51	Yes	No	Yes	Yes	No	Yes
Windows 98	No	Yes	Yes	Yes	Yes	No
Windows 95	No	Yes	Yes	Yes	Yes	No
Windows 3,x & WFW	No	No	Yes	Yes	No	No
OS/2	No	No	Yes	Yes	No	Yes
MS-DOS	No	No	Yes	Yes	No	No

The FAT file system does not support file compression on Windows 2000 systems. The file compression utilities with Windows 95 and Windows 98 are not supported by Windows 2000.

FAT file systems may be converted to NTFS file systems using the command line convert utility. Once converted, they may not be changed back to FAT.

Windows 2000 contains an NTFS file defragmentation utility which Windows NT does not contain.

Support for Security

Each object has an Access Control List (ACL) which defines users and group permissions for the object. Each entry (ACE - Access Control Entry) in an ACL defines the permissions a specific user or group has for the object. Access token attributes are added to the object's ACL. The user's security identifier (SID) is compared to the contents of the ACL to determine if the user has the correct privileges to access the object.

The NTFS file system supports Access Control Lists for objects.

Volumes

A volume and a partition are the same thing. It is a formatted part of a disk that appears as one drive. Volume types supported by Windows 2000 include:

• Simple volumes - Formatted partition on a hard drive. Has no fault tolerance.
• Spanned volumes - Space on multiple disk drives that appears as one drive.
• Striped volumes - Identical sized areas of two or more hard drives that appear as one although part of the data is stored on each drive in a way so data is written to both at the same time. This is used to increase drive speed.
• Mirrored volumes - Also known as RAID 1 or a mirror set on Windows NT, this is a fault tolerance method where data is stored on two volumes (that appear as one) rather than a single volume. This costs access time, but is fault tolerant.
• RAID-5 Volumes - Require three or more areas of formatted drive space. Generating parity information can cost processor time.

A normal hard disk can contain up to four partitions total. It can contain one extended partition which can be further broken up into additional logical drives. It can contain four primary partitions or three primary partitions and one extended partition.

Disk Tools

The Computer Management Console Tools, Storage section describes these tools in greater detail.

• Disk Defragmenter - Used to analyze volumes and defragment the disk.
• Disk Management - Used to create, format, and manage volumes.
• Logical Drives
• Removable Storage