To answer your question on Dynamic disks, I pulled this information from an EMC White Paper several of my team wrote earlier this year:
Microsoft Windows 2000 and Windows/XP Pro supports two types of disk storage: Basic disks and Dynamic disks.
Basic disks are the format used by Windows NT 4.0. Dynamic disks are new with Windows 2000, and offer more functionality than Basic disks. Windows 2000 uses the Logical Disk Manager (LDM) service to create and manage Dynamic disks and Basic disks. LDM is management software written by VERITAS and shipped by Microsoft in Windows 2000. VERITAS also offers an extended set of capabilities for Dynamic disks, which is delivered through a
separately purchased software product named VERITAS Volume Manager for Windows 2000.
A Basic disk is a physical disk that contains primary partitions, extended partitions, or logical drives. Basic
disks may be accessed from Windows XP, Windows 2000, Windows NT 4.0, or MS-DOS. Basic disks are formatted with
partitions using Disk Administrator on Windows NT 4.0 systems, or with LDM on Windows 2000/XP systems.
A drive letter is associated with a partition when it is mounted on a server. With Windows 2000/XP, the
partitions on a Basic disk may be configured into:
? Simple volumes
? Spanned volumes (called volume sets on Windows NT 4.0)
? Mirrored volumes (called mirror sets on Windows NT 4.0)
? Striped volumes (called stripe sets on Windows NT 4.0)
? RAID 5 volumes (called stripe sets with parity on Windows NT 4.0)
On Windows 2000/XP, Basic disks can include those created on Windows NT 4.0 and those created on
Windows 2000/XP. When a Basic disk created on Windows NT 4.0 is imported onto a Windows 2000/XP system,
the partitions are hard-linked and cannot be extended.
Basic disks are accessible from Windows 98, Windows NT, and Windows 2000/XP.
Dynamic Disks
A Dynamic disk is a physical disk that contains Dynamic volumes created using the LDM. Dynamic disks
can contain an unlimited number of volumes, so you are not restricted to four volumes per disk. Dynamic
disks are not supported on portable computers. Dynamic disks that are created by upgrading a Basic disk to a Dynamic disk have partitions that are called hard linked. Pure Dynamic disks (those that are created new on Windows 2000/XP) have only a single partition table entry to define the entire disk. Volumes contained on a pure Dynamic disk are called soft-linked and do not display drive letters until they are mounted by the LDM.
Dynamic disks are accessible only from Windows 2000.
Configuration Information Reserved Space
Configuration information for Basic disks is stored in the master boot record, which is the first sector of the
disk. Windows NT 4.0 fault-tolerant disk sets store additional partition relationship information in the first
track of the disk. Dynamic disks reserve a 1 MB region at the end of each Dynamic disk for configuration. The disk group
information is stored in this region. When a Basic disk is imported into Windows 2000/XP, space is reserved at the end of the disk for future upgrades to a Dynamic disk.
Types of Volumes on Disks
Basic disks on Windows NT 4.0 are formatted into partitions (either primary partition or extended
partition) and are referenced as logical drives with a drive letter. On Windows 2000/XP, Basic disks can also
be mounted to an empty folder (reparse point).
A Dynamic disk is formatted with volumes. Volumes can be mounted to a drive letter or to an empty
folder in an NTFS on another volume.
Partitions on Windows NT 4.0 can be organized into fault-tolerant configurations called volume sets, stripe
sets, mirror sets, and stripe sets with parity. On Windows 2000, these constructs are called, respectively,
spanned volumes, striped volumes, mirrored volumes, and RAID 5 volumes. The terminology is different,
but the fault tolerance is the same.
Simple Volume
A volume is a storage unit made from free space on one or more disks. It can be formatted with a file
system and assigned a drive letter, or mounted to an empty folder on another volume. Volumes on Dynamic
disks can be a simple volume or a volume set.
A simple volume is made up of disk space on a single physical disk. It can consist of a single region on a
disk or multiple regions on the same disk that are linked together. It can be extended on the same disk or
onto additional disks. If you extend a simple volume across multiple disks, it becomes a volume set.
Volume Sets
Volume sets can be of several types. Windows 2000 can access volume sets residing on either Basic or
Dynamic disks, but LDM can only create volume sets from Dynamic volumes.
A spanned volume is made up of disk space that is linked together from multiple disks (up to 32 disks with
Windows 2000 currently, or an unlimited number of disks with VERITAS VxM). It can be extended in size
dynamically.
In Windows NT 4.0 and earlier, a spanned volume was known as a volume set. The term volume set is used
herein to describe multidisk volumes on either Windows NT 4.0 or Windows 2000.
You can extend a simple or spanned volume only if the volume was created on a Dynamic disk. You
cannot extend a simple or spanned volume that was upgraded from Basic to Dynamic. When any Windows
NT 4.0 volume set is imported to Windows 2000, the underlying disk may be upgraded to a Dynamic disk
or may be left in the Basic disk format, at the user's choice.
A striped volume stores data in stripes on two or more physical disks. Data in a striped volume is allocated
alternately and evenly (in stripes) to the disks of the striped volume. Striped volumes substantially improve
the speed of access to your hard disk. Striping is also known as RAID 0.
In Windows NT 4.0 and earlier, a striped volume was known as a stripe set.
A mirrored volume is a fault-tolerant simple volume whose data is duplicated on two physical disks. It
provides data redundancy by using a copy (mirror) of the volume to duplicate the information contained in
the volume. The mirror is located on a different disk. If one of the physical disks fails, the data on the failed
disk becomes unavailable, but the system continues to operate using the unaffected disk. Mirroring is also
known as RAID 1. A mirrored volume cannot be extended with LDM, but can be extended with VERITAS
VxM.
In Windows NT 4.0 and earlier, a mirrored volume was known as a mirror set.
A RAID 5 volume is a fault-tolerant spanned volume with data and parity striped intermittently across three
or more physical disks. If a portion of a physical disk fails, the data that was on the failed portion can be
recreated from the remaining data and parity. A RAID 5 volume cannot be mirrored. It cannot be extended
with LDM. It can only be extended with VERITAS VxM. With VERITAS VxM, the size of each column
can be extended, but not the number of columns.
On Windows NT 4.0 and earlier, a RAID 5 volume was known as a stripe set with parity.
Facebook
Twitter