A+ Guide to Managing and Maintaining Your PC Fifth Edition Chapter 9 Optimizing and Protecting Hard Drives

2 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Hands-on Project: Install a Slave Drive

3 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Managing Hard Drives Disk defragmentation ScanDisk Disk Cleanup Disk compression Disk caching Disk cloning Making backups

4 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Fragmentation Desirable A file is placed in contiguous clusters A file is placed in discrete clusters Fragmented Slow down access time Complicate recovery of a corrupted file

5 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Windows Defragmenter

6 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Hands-on Project: Defragmenter pp. 360 Start->All Programs->Accessories->System. Tools->Disk Defragmenter Do a fragmentation analysis

7 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Cross-Linked and Lost Clusters

8 A+ Guide to Managing and Maintaining Your PC, Fifth Edition ScanDisk 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

9 A+ Guide to Managing and Maintaining Your PC, Fifth Edition ScanDisk

10 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Hands-on Project: ScanDisk pp. 362 Windows Exploer->right –click the drive-> Properties->Tools tab->Check Now under Error-checking->check the two check-boxes

11 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Clean Up Disks Delete temporary files to free up space

12 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Disk Cleanup

13 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Hands-on Project pp. 364 Windows Explorer-> right-click the drive- >Properties->General tab->Disk Cleanup

14 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Disk Compression Save hard drive space May loose data May result in longer disk access time

15 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Hand-on Project: Compress an NTFS Drive Windows XP/2000 pp. 366 Explorer->Properties- >General->Check “Compress drive to save disk space”

16 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Hands-on Project: Compress a File/Folder in Windows XP/2000 pp. 366 Explorer->Properties- >General->Advanced- >Check “compress contents to save disk space”

17 A+ Guide to Managing and Maintaining Your PC, Fifth Edition 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

18 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Disk Caching

19 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Hardware Cache Built in the hard drive controllers The BIOS on the controller contains the cache program RAM chips on the controller hold the cached data

20 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Software Cache A software that is loaded into the memory during boot-up Uses system RAM to hold the cached data

21 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Hardware Cache vs. Software Cache Advantages: does not use system RAM Disadvantages  Slower  Impractical to update

22 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Disk Caching in Windows Windows NT/2000/XP: automated disk caching Windows 9x: VCACHE

23 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Hands-on Project: Enable Disk Cache pp. 367 and Figure 9-9

24 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Backups A backup is an extra copy of a file The backup can be used to recover the original file if it is damaged

25 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Backup Types Full backups: back up all data from hard drive Incremental backups: back up only files that have changed or been created since last backup Differential backups: back up files that have changed or been created since the last full backup

26 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Example Backup Methods Perform a full backup every Friday, and incremental backups Monday through Thursday Perform a full backup every Friday, and differential backups Monday through Thursday Discussion: advantages and disadvantages of each method?

27 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Hands-on Project: Windows 2000/XP Backup pp

28 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Disk Cloning (Disk Imaging) Replicates a hard drive to multiple computers Software for disk cloning  Drive Image by PowerQuest  ImageCast by Innovative Software  Norton Ghost by Symantec Corp

29 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Computer Infestations Any unwanted program transmitted to a computer without the knowledge of the user Are designed to do varying degrees of damage to data and software Do not damage hardware The hard drive may appear to be physically damaged when the boot sector information is destroyed

30 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Computer Infestations Virus Needs a host program Infected program must be executed for a virus to run replicates by attaching to other programs Has an incubation period (does not do damage immediately) Worm Spreads copies of itself without a host program Does damage by overloading the network or the system Best defense is a firewall Trojan horse Substitutes itself for a legitimate program Does not need a host program to work Most cannot replicate Logic bomb Dormant code added to software; triggered at a predetermined time or by a predetermined event

31 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Virus Types Boot sector viruses  The Master Boot Record program  The OS Boot Record program File viruses  Executables (.exe,.com, or.sys)  Word files containing macros (Macro viruses) Multipartite viruses

32 A+ Guide to Managing and Maintaining Your PC, Fifth Edition How a Virus Replicates Non-memory- resident virus Memory- resident virus

33 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Anti-virus Software Looks for distinguishing characteristics (virus signatures) Looks for a program that can replicate itself Monitors the difference between a program’s file sizes

34 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Virus Cloaking Techniques Polymorphic viruses – changes its distinguishing characteristics as it replicates Encrypting viruses – transform itself into a nonreplicating program Stealth viruses  Alters OS to mask the size of the host file  Resets the host file before it is opened

35 A+ Guide to Managing and Maintaining Your PC, Fifth Edition How a Worm Gets into Your Computer

36 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Virus Hoaxes warnings about a nonexistent virus Overload network traffic Check Web sites that specialize in debunking virus hoaxes

37 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Protecting Against Computer Infestations Do not run programs or attachments unless you are sure that they are safe Implement a firewall to protect ports  Open only necessary ports to specific IP addresses Keep Windows current with updates and patches Install and run an anti-virus software

38 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Damaged Partition Table Messages - Invalid drive or drive specification Solutions  A> Fdisk /Mbr  Recovery Console: fixmbr

39 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Damaged OS Boot Record Messages  Invalid media type  Non-DOS disk  Unable to read from Drive C Solutions  Recover from backup  Third-party software

40 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Damaged FAT, Root Directory, or Bad Sectors Messages  Sector not found reading drive C  Bad sector Solutions  Scandisk  Third-party recovery software

41 A+ Guide to Managing and Maintaining Your PC, Fifth Edition Damaged System Files Messages  Non system disk or disk error  Invalid system disk Solutions  Copy systems to the drive by sys C: