Windows 7 Chapter 4

Front 1

basic disk

Back 1

Most Windows computers use basic disks because they are the easiest to manage. A basic disk uses primary partitions, extended partitions, and logical drives to organize data.

Front 2

Diskpart.exe

Back 2

Diskpart.exe is a powerful utility that can perform any task the Disk Management snap‐in can and more. For example, Diskpart enables you to create a fourth primary partition on a basic disk, rather than an extended partition and a logical disk.

Front 3

dynamic disk

Back 3

A dynamic disk is able to contain an unlimited number of volumes that function like primary partitions on a basic disk. However, you cannot access a dynamic disk from any operating system instance other than the one that converted it from basic to dynamic, which means you cannot use dynamic disks on multiboot systems.

Dynamic disks can support five types of volumes: simple, spanned, striped, mirrored, and RAID‐5 (Redundant Array of Independent Disks, level 5). Windows 7 only supports four of these volume types, however: simple, spanned, striped, and mirrored.

Front 4

exFAT

Back 4

Introduced in Windows Vista SP1, the Extended File Allocation Table (exFAT) file system, also known as FAT64, is a 64‐bit FAT implementation that is intended primarily for large USB flash drives. The theoretical limitations of exFAT are partitions and files of up to 64 zettabytes in size. (1 zettabyte equals 1 billion terabytes or 1021 bytes.) The recommended maximum size for an exFAT partition in Windows 7 is 512 TB. The exFAT file system does not support the encryption and permission features found in NTFS, and is therefore not recommended for use on Windows 7 hard disks.

Front 5

FAT (file allocation table)

Back 5

The original 16‐bit FAT file system for hard disks, also known as FAT16, is limited to partitions no larger than 4 GB, which makes it virtually useless for today's computers.

Front 6

FAT32

Back 6

Using the 32‐bit version of FAT, called FAT32, Windows 7 can create partitions up to 32 GB in size, with individual files up to 4 GB. Although these limits at one time seemed outlandishly large, they make FAT32 an impractical file system solution on computers today. The 32 GB maximum partition size is a deliberate restriction in Windows 7, not an inherent limitation of FAT32. In fact, Windows 7 can access FAT32 partitions up to 2 TB in size; it just can't create them. This limitation is intended to prevent Windows performance degradation caused by large FAT32 partitions.

Front 7

globally unique identifier (GUID)

Back 7

First introduced in Windows Vista, you can now use the GPT partition style on x86‐, as well as x64‐based, Windows 7 computers.

Front 8

GUID (globally unique identifier) partition table (GPT)

Back 8

Supports up to 128 primary partitions

Supports volumes up to 18 exabytes in size

Data critical to platform operation is stored in partitions rather than in hidden sectors

Replication and cyclical redundancy check (CRC) protection of the partition table provide increased reliability

Front 9

master boot record (MBR)

Back 9

This is the default partition style for x86‐based and x64‐based computers.

Supports up to four primary partitions or three primary partitions and one extended partition, with unlimited logical drives on the extended partition

Supports volumes up to 2 terabytes in size

Data critical to platform operations is stored in hidden (unpartitioned) sectors

Replication and CRC are not features of MBR's partition table

Front 10

mirrored volume

Back 10

RAID 1. Consists of an equal amount of space from 2 disks, both of which must be dynamic disks. In a mirrored volume, each disk holds an identical copy of the data written to the volume as a fault tolerance measure. If one disk fails, the data remains accessible from the second disk. Because of the data redundancy, a mirrored volume only provides half as much storage space as any of the other volume types.

Front 11

native boot

Back 11

The Windows 7 Enterprise and Ultimate editions also include support for VHD files, using a feature called native boot, which enables you to create and modify VHDs in Windows 7 and even boot Windows 7 from a VHD, all without having to run a virtual machine manager product such as Virtual PC or a hypervisor‐based product such as Hyper‐V.

Front 12

NTFS

Back 12

NTFS is the preferred file system for Windows 7; its main benefits being improved support for larger hard drives and better security in the form of encryption and permissions that restrict access by unauthorized users.

Front 13

simple volume

Back 13

Consists of space from a single disk. Once you have created a simple volume, you can later extend it to multiple disks to create a spanned or striped volume, as long as it is not a system volume or boot volume. Windows 7 supports simple volumes on both basic and dynamic disks.

Front 14

spanned volume

Back 14

Consists of space from at least 2, to a maximum of 32, physical disks, all of which must be dynamic disks. A spanned volume is essentially a method for combining the space from multiple dynamic disks into a single large volume. Windows 7 writes to the spanned volume by filling all of the space on the first disk, and then filling each of the additional disks in turn. You can extend a spanned volume at any time by adding additional disk space. Creating a spanned volume does not increase the read/write performance, nor does it provide fault tolerance. In fact, if a single physical disk in the spanned volume fails, all of the data in the entire volume is lost.

Front 15

striped volume

Back 15

RAID 0. Consists of space from at least 2, to a maximum of 32, physical disks, all of which must be dynamic disks. The difference between a striped volume and a spanned volume is that in a striped volume, the system writes data one stripe at a time to each successive disk in the volume. Striping provides improved performance because each disk drive in the array has time to seek the location of its next stripe while the other drives are writing. Striped volumes do not provide fault tolerance, and you cannot extend them after creation. If a single physical disk in the striped volume fails, all of the data in the entire volume is lost.

Front 16

Virtual Hard Disk (VHD)

Back 16

A VHD file contains the entire contents of a hard disk in a single, portable file that administrators can use to move entire virtual machines (VMs) from one host computer to another. In the logical environment of a virtual machine, a VHD functions exactly like a hard disk drive does in a physical machine