Windows 9X File System

Introduction to file systems

• Windows 9x provides a number of features to prepare your hard drive  for use and to maintain your information  after the installation  of the operating system  optimally.

• The operating system  (OS) preparation tools for your hard drive  include FDISK.EXE  and FORMAT .COM .

• The Maintenance tools of windows include Scandisk , Defrag, backup, and also the ability of disk caching.

• Windows 9x also has improved storage features such as Long File Names (LFN ), disk compression on FAT16  and the inclusion of the efficient FAT32  filing system.

 

Partitioning  Your Hard Drive High Level Format The IFSHLP .SYS  file FAT 16 FAT 32 Disk Caching

Disk Compression Long File Names CDFS Scandisk Backup Defragmentation

 

There are three stages in preparing a hard drive ,

a)      Low Level Format (LLF )- Usually Performed by manufacturer, can be done in the BIOS  Basic Input Output System

b)      Partitioning  –Performed by DOS  or Windows 98 using FDISK.EXE

c)      High Level Format (HLF ) –Performed by the operating system  after partitioning

 

Low Level Format (LLF )

• The sector ID’s are defined during LLF . These sectors  ID’s are used as landmarks for finding data by all operating systems on the hard drive .

• LLF  is usually performed by the manufacturer but can be performed by the BIOS

• LLF  is not recommended accept as a last resort.

Partitioning  your Drive

• Partitioning  is a process of dividing a drive into separate sections.

• It’s ideal for dual booting environments and different filing systems such as FAT16 , FAT32 , and NTFS .

• Partitioning  is very useful for inefficient filing systems such as FAT16 .

• A program called FDISK.EXE  in DOS  and windows 95/98 performs partitioning.

• A Hard drive, which contains partitions, is a Basic Disk.

• Hard drives can have only primary and extended partitions .

• FDISK.EXE  will allow you to create one primary partition  and one extended DOS  partition although your drive can contain up to four primary partitions.

• All partitions must exist within the primary and extended partitions .

• Logical drive can exist inside the extended partition

• Partitioning  your hard drive  with Fdisk.exe available in DOS  windows 95/98. Refer to the partitioning module  for more information .

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Exercise (Using FDISK from windows 98 startup  disk to view partition information )

Boot from the windows 98 startup  disk Once you have booted up with CD  ROM  support type the FDISK.EXE  command If your hard drive  is larger than 528MB the program will inform you of windows support for large drives and the ability of using FAT32  filing system. Once you press y for yes the typical FDISK screen will appear. The Fdisk screen has 4 options which are: - Create DOS  partitions Set active partition Delete DOS  partitions View drive partitions Select option 4 to view current partition information .

 

Exercise (Creating DOS  Partitions)

From the Fdisk main screen select the first option that is create partitions. You will now have 3 options available to you Create Primary DOS  partition Create Extended  DOS  partition Create Logical drives in the extended DOS  partition Select option 1 to create a primary DOS  partition You will now have the option of making the whole drive 1 primary partition  select no on that option Now define the size of your primary DOS  partition e.g. 200MB Select option 1 from the main menu to create partitions Select option 2 to create an extended DOS  partition e.g. 300MB If you are using windows9x as your only operating system  then make sure the entire hard drive  space is covered by the primary and extended DOS  partitions. You can now define the sizes of your logical drives in the extended DOS  partition by selecting the option of create logical drive in extended DOS partition. Finally from the main menu select option 2 to set the active partition which is the primary DOS  partition.

 

Deleting DOS  partitions

From the Fdisk main screen select option 3 to delete partitions You must follow the reverse order to creating partitions, when deleting partitions, You must first remove the logical drives, then the extended DOS  partition and then Finally you can delete the primary DOS partition and exit the environment.

 

High Level Format

• High Level Format (HLF ) is always performed by the operating system  (OS) of interest. (HLF) Writes on the disk the filing structure used by that particular OS which allow files  to be written located on the disk, also creates boot records, and a directory  system.

 

Exercise (Formatting a Diskette in Windows 9x)

Double click on the My computer icon Place a diskette in the floppy drive Right click on the A: drive and choose format  from the drop down menu From the format  window click on the start button

Installable File System Helper (IFSHLP .SYS )

• This file enables the operating system  to expand its access capabilities to the storage devices  that were minimal with only IO.SYS  handles available.

• IFSHLP .SYS  enables the OS to access others filing systems such as FAT16 , FAT 32, CDFS , and VFAT  and also some of the peripherals  and networking features of the computer.

• It can communicate with other vendor filing systems such as UNIX  and Apple Macintosh .

File Systems

• There must exits a filing system to store your files  on to the disk. The filing system organizes the disk and provides a framework for viewing, storing and accessing files on the hard drive .

• All computer operating system  software  vendors provide their own filing system and some can access files  from other vendor filing systems such as Macintosh machines.

• We will be dealing with windows 9x  a supported filing system that is either FAT16  or FAT32 .

File Allocation Table (FAT)

• FAT is the simplest way of organizing the storage space on the hard drive  when dealing with files  and folders .

• FAT contains a table of content listing the cluster location of all files  recorded on the storage medium .

FAT12 and FAT16

• DOS  initially used FAT12 as its filing system designed for floppy disks which where the standard medium of that time and can only exist on partitions sizes smaller the 16MB.

• FAT 16 was developed for DOS  version 3 and above supporting partition sizes of 2GB and a hard drive  size of 4GB.

File Allocation Table (FAT32 )

• FAT32  supports drive sizes of up to 2 Terabytes TB.

• FAT 32 uses a more efficient way of saving files  reducing the cluster size to a uniform 4KB in small and large drives.

• FAT32  is made more stable and less susceptible to a single point of failure then FAT by extending the boot records to include the backup of the critical data structure

• Table of comparison of cluster size change with volume size for FAT16  and FAT32  partitions.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

• Since FAT32  is a more efficient filing system than FAT16 , it will be advantageous to convert  to a FAT32 filing system in drives larger then 512MB that are not dual booting between DOS  and Windows.

• FAT32  Does not support partitions smaller then 512 MB

• You can convert  to FAT32  in two separate ways:

• Run Windows 9x FDISK.EXE  utility, which means all data, is lost and then install Windows 9x.

• Uses the convert  tool  inside Windows 9x that is demonstrated next.

 

Exercise (Converting to FAT32  using the Drive Converter)

1.      Click on startà programs à accessoriesàSystem toolsàdrive converter 32 2.      Follow the steps of the wizard to convert  the filing system to fat 32

Disk Caching and Swap  files

• Swap  files  are spaces used from the hard drive  designated as virtual RAM .

• If your system runs out of memory  using swap files  means that your system does not halt but only slows down because it stores some of its data on the hard drive  emulating your RAM .

• Usually your windows 9x  Operating System automatically allocates 1.5 to 2 times the amount of your system RAM  from the hard drive  if available and designates it as a swap file and manages your swa