Optimizing and Protecting Hard Drives

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Chapter 9

• Optimizing and Protecting Hard Drives

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You Will Learn

• About supporting hard drives and making backups
• About viruses and other computer infestations,
  and how to protect against them
• How to troubleshoot hard drives

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Managing Hard Drives

• Use Windows utilities to protect, optimize, and
  maintain hard drives
• Defrag and Windows Disk Defragmenter
• ScanDisk
• Disk Cleanup
• Disk compression
• Disk caching
• Making backups
• Access utilities from command prompt or Windows
  desktop

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Defrag Command and Windows Disk Defragmenter

• Detects and repairs fragmentation, which can slow
  down access time and complicate recovery of a
  corrupted file
• Defragment hard drive once a month

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ScanDisk

• Designed to replace Chkdsk command
• Repairs cross-linked and lost clusters
• Checks FAT for problems with long filenames and
  the directory tree
• Scans the disk for bad sectors
• Repairs problems with structure of a hard drive
  that has been compressed using Windows DriveSpace
  or DoubleSpace

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Cross-Lined and Lost Clusters
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ScanDisk Results
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ScanDisk in MS-DOS Mode
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Disk Cleanup
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Disk Compression Methods

• Store data on hard drive in one big file
• Manage writing of data and programs to that file
• Rewrite data in files in mathematically coded
  format that uses less space

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Disk Compression

• Disk compression in Windows XP and Windows 2000
• Use the NTFS file system
• Disk compression in Windows 9x
• Use DriveSpace utility on a FAT 16 file system

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Disk Cache

• Temporary storage area in RAM for data being read
  from or written to a hard drive
• Speeds up access time to the drive

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Disk Caching
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Disk Caching (continued)

• Hardware cache versus software cache
• How disk caching methods have changed
• DOS
• DOS with Windows 3.x
• Windows 9x
• Windows NT/2000/XP

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Making Backups

• Child, parent, grandparent method
• Full, incremental, and differential backups
• Scheduling backups
• Backup software
• Disk cloning software
• Planning for disaster recovery

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Child, Parent, Grandparent Method
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Full, Incremental, and Differential Backups

• Full
• Backs up all data from hard drive
• Incremental
• Backs up only files that have changed or been
  created since last backup
• Differential
• Backs up files that have changed or been created
  since the last full backup

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Scheduling Backups
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Scheduling Backups (continued)
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Scheduling Backups (continued)
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Backup Software

• Comes with most tape drives
• Third-party software also available
• Backup utilities are provided with Windows
  NT/2000/XP and Windows 9x

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Windows 2000/XP Backup Utility

• Can perform immediate backup from Backup tab
• Can schedule repeated backups

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Disk Cloning Software

• Replicates hard drive to a different computer or
  to another drive on the same computer
• Examples
• Drive Image by PowerQuest
• ImageCast by Innovative Software
• Norton Ghost by Symantec Corp

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Planning for Disaster Recovery

• Verify your recovery plan
• Keep a record of regular backups
• Folders or drives backed up
• Date of the backup
• Type of backup
• Label identifying the tape, disk, or other media

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Viruses and Other Computer Infestations
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Understanding Computer Infestations

• Where viruses hide
• Boot sector viruses
• File viruses
• Multipartite viruses
• Cloaking techniques
• Polymorphic viruses
• Encrypting viruses
• Stealth viruses
• Potential damage ranges from minor to major

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How Infestations Spread

• User activities can increase susceptibility
• Virus replicates
• A Trojan horse gets into your computer
• A worm gets into your computer

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How a Virus Replicates
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How a Worm Gets into Your Computer
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Virus Hoaxes

• E-mail warnings about a nonexistent virus
• Overload network traffic
• Check Web sites that specialize in debunking
  virus hoaxes

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Protecting Against Computer Infestations

• Make backups
• Use antivirus software regularly
• Keep Windows current with updates and patches
• Implement a firewall

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Protecting Against Computer Infestations
(continued)

• Be aware of virus symptoms
• Know what to do when you suspect a virus
  infestation
• Run antivirus software
• Check Web site of AV software manufacturer
• Use antivirus software

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Capabilities to Look for When Selecting Antivirus
Software

• Download software upgrades and virus definitions
  from the Internet
• Automatically execute at startup
• Detect macros in word-processing documents
• Automatically monitor files being downloaded from
  the Internet
• Send virus alerts to your e-mail address
• Scan both automatically and manually

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General Troubleshooting Guidelines

• Make backups and keep them current
• Run antivirus software regularly
• Defragment files and scan the hard drive
  occasionally
• Dont smoke around your hard drive
• Dont leave the PC turned off for weeks or months
  at at time

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General Troubleshooting Guidelines (continued)

• High humidity can be dangerous for hard drives
• Be gentle with a hard drive
• Take precautions when moving a hard drive or
  changing CMOS setup

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Resolving Common Hard Drive Problems

• Categories of problems
• Caused by hardware or software?
• Prevent hard drive from booting or prevent data
  from being accessed?
• Gather basic information from user diagnose and
  address the problems
• Focus on the main priority
• Use available resources (documentation,
  manufacturers Web site, technical support)

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Troubleshooting Hard Drives with Third-Party
Software

• Norton Utilities
• SpinRite
• PartitionMagic

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Hardware Problems

• Hard drive not found
• Invalid drive or drive specification
• Damaged boot record
• Damaged FAT or root directory or bad sectors
• Cannot boot from the hard drive
• Drive retrieves and saves data slowly

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Software Problems with Hard Drives

• Corrupted OS files
• Corrupted partition table, boot record, or root
  directory, making all data on the hard drive
  inaccessible
• Corrupted area of the FAT that points to the
  data, datas directory table, or sector markings
  where data is located
• Corrupted data

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Resolving Hard Drive and Data Access Problems

• Partition table
• Boot record
• FAT and root directory
• System files
• Data and program files

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Data and Program File Corruption

• Options for restoring a data file that is not
  backed up
• OS system tools and commands
• Third-party software
• Professional data recovery service

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Data and Program File Corruption (continued)

• Recovering data when portions of a damaged file
  are still intact
• Create a new file on another disk
• Use Copy command
• Edit new file to replace missing data

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Data and Program File Corruption (continued)

• Potential problems with files and file system
• Corrupted file header
• Lost clusters
• Erased file

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Getting Technical Support

• Before you call, have available
• Drive model and description
• Manufacturer and model of computer
• Exact wording of error message
• Description of the problem
• Hardware and software configuration for the system

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Summary

• How to optimize hard drive performance through
  disk compression and caching of hard drives
• Types of viruses that can infect your hard drive
  how to remove and prevent them
• What to do when a hard drive fails or produces
  errors
• The importance of keeping reliable backups of the
  file system and data