Transcript File - Computer Maintenance

Computer Maintenance
Disk Operating System (DOS)
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Computer Maintenance
Disk Operating System (DOS)
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Brief History of Microsoft’s
Operating Systems
I. MS-DOS
After shaking hands with the IBM representatives, Microsoft cofounder/CEO, Bill Gates began to search for an OS (operating
system) compatible with Intel’s 8086 microprocessor. What he
found was a primitive OS made by a small shop owner called
QDOS (Quick-and-Dirty Operating System). He bought the
rights to it for a few thousand dollars. After a few minor
changes, Microsoft released their very first edition of MS-DOS
(Microsoft Disk Operating System) version 1.1. All though a
primitive OS by today’s standards, it performed all the required
operations for an OS.
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Brief History of Microsoft’s
Operating Systems
I. MS-DOS
Through the years MS-DOS went through a variety of changes
until Microsoft released its final pure DOS version,
6.22. Microsoft made a deal with PC vendors that when they
sold a PC a version of MS-DOS installed on the machine, until
MS-DOS 5.0 you could not purchase MS-DOS in a store! DOS
is a text based single-tasking operating system, meaning you
can only run one program at one time.
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Brief History of Microsoft’s
Operating Systems
II. Windows Generation 1 (Windows 3.x)
The first 5 versions of Windows (3.0, 3.1, for Workgroups
3.1, 3.11, for Workgroups 3.11), referred to as Windows 3.x,
all need DOS installed to run because they were designed
an add-on for DOS not as a standalone OS. The first
version of Windows was simply for managing files & running
programs and did not have any memory-management
features and was therefore not capable of multi-tasking. The
“For Workgroups” edition to Windows had added features for
networking a LAN.
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Brief History of Microsoft’s
Operating Systems
III. OS/2
In the mid 1980’s Microsoft & IBM were working on an OS
that, at the time, they thought would make DOS
obsolete. This OS was called OS/2. The first versions of
Windows were little more than test-beds for OS/2. OS/2 was
designed to take advantage of the advanced functions of
Intel’s 286 microprocessor. The success of Windows made
Microsoft ambitious and IBM nervous, causing friction in
their alliance. In 1992 IBM took OS/2 and without the help
of Microsoft, improved it with version 2.20 claiming it ran
Windows applications better than Windows but without the
use of DOS. It quickly flopped in the markets.
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Brief History of Microsoft’s
Operating Systems
IV. Windows Generation 2 (Windows 9x)
Microsoft decided instead of confusing end-users with version
numbers, their products would now carry a year of its
release. Hence the Windows 95, it had some significant
changed to its interface which made it look more like Mac
or OS/2, but existing programs designed for Windows 3.x ran
much slower on Windows 95, nor was it compatible with
hardware which was used on Windows 3.x , it also lacked the
use of some utilities. Regardless of the downsides Windows
yet again took the market by storm.
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Brief History of Microsoft’s
Operating Systems
IV. Windows Generation 2 (Windows 9x)
The next Windows made in 98 was named Windows 98 and is
today the most popular OS. Windows 98 was basically
Windows 95 revised, revised, & revised again, with added
features. It cleared up a lot of bugs and problems that were
unknown with the launch of Windows 95. Windows 95/98 is
commonly referred to as Windows 9x because they are so
similar.
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Brief History of Microsoft’s
Operating Systems
V. Windows Generation 3
The cousin to Windows 95 was another OS for Networking
which was called Windows NT, it had added features for
networks, but lacked the compatibility with some Windows
95/98 programs. This is where a lot of people get confused
with which OS is the correct OS for them. Windows 3.x for
Workgroups and Windows NT were designed for networking
and for corporate machines.
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Brief History of Microsoft’s
Operating Systems
V. Windows Generation 3
Windows 2000 and Windows Millennium Edition are often
confused with each other. You would think that since
Windows 2000 is named for the year 2000 it was the next
step up from 98, right? Wrong!
It’s actually a step up from Windows NT. It was “built on NT
technology” and therefore has added features that the
average home user will never use! While all-in-all one of the
best OSs, it was not designed for home use. Windows 2000
is often referred to as W2K or Win2K.
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Brief History of Microsoft’s
Operating Systems
V. Windows Generation 3
Millennium Edition (Windows ME) has a bad name in the
industry because Microsoft rushed to get it out on the market
so that people wouldn’t buy Windows 2000 thinking it was
for home use. Well the theory is that since they rushed it
must have bugs. ME was an upgrade to Windows 98.
Whether or not Windows ME has more bugs than most we
may never know.
Win2K and ME both have a unique feature called System
Restore which will restore the system back to a previous
state, a great tool that until Win2k and Win ME was only
available through 3rd party software like Adaptec’s Go Back.
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Brief History of Microsoft’s
Operating Systems
VI. Windows Generation 4
Windows eXPerience or Windows XP for short is a “Hybrid”
OS. It is an upgrade to Windows 2000 and NT. It’s a hybrid
because it has the compatibility of Windows 98, the stability
and security of Windows 2000.
Windows XP Home Edition is for the home user, and
Windows XP Professional is for networking and corporate
use.
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DOS
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DOS Development Timeline
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Boot Process
1.
2.
3.
4.
BIOS runs POST
BIOS loads the MBR into memory
MBR starts IO.SYS
IO.SYS starts MSDOS.SYS
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Boot Process
5.
6.
7.
MSDOS.SYS initializes hardware
MSDOS.SYS looks for and runs
CONFIG.SYS (if present)
IO.SYS regains control and it loads
COMMAND.COM
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Boot Process
8.
9.
COMMAND.COM looks for and runs
AUTOEXEC.BAT (if present)
The DOS shell is complete and the
Prompt is displayed
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Function Keys
The special function keys available during the DOS Startup
are summarized as follows:
F5 (also Left Shift key) – Skips CONFIG.SYS and AUTOEXEC.BAT
files
F8 – Proceeds through the CONFIG.SYS and AUTOEXEC.BAT
files one step at a time waiting for Confirmation form the user.
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Boot Order
The following list summarizes the files
and their execution order required for
bootup in an MS-DOS system:
• IO.SYS
• MSDOS.SYS
• CONFIG.SYS
• COMMAND.COM
Remember the files
involved the DOS
bootup process
and the order of
their execution.
• AUTOEXEC.BAT
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Assigning and Using Filenames
1. All files must have a filename.
2. All filenames must be different than any other filename
in the system, or on the disk presently in use.
3. DOS filenames are up to 8 characters long with an
optional 3-character extension (separated from the
basic filename by a period).
4. When using a filename in a command, you must also
use its extension, if one exists.
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Assigning and Using Filenames
5. Some special characters are not allowed in filenames.
These are: [ ] : ; + = \ / > ? ,
6. When telling DOS where to carry out a command, you
must tell it on which disk drive the operation is to be
performed. The drive must be specified by its letter name
followed by a colon (A: or C:).
7. The complete and proper way to specify a file calls for the
drive specifier, folder, subfolder, the filename, and the filename extension, in that order ( B:filename.ext).
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DOS Commands
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Command Switches
A
switch is added to the command
by adding a space, a fore-slash (/),
and a single letter:


COMMAND (space) option /switch
Common DOS command switches include
/P for page, /W for wide format, and /S for
system. Different switches are used to
modify different DOS commands. In each
case, the DOS User’s Guide should be
consulted for switch definitions available
with each command.
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DOS Commands
Command
Type
Function
DIR
Internal Displays the contents of a directory
CD
Internal Changes to a specified directory
MD
Internal Creates a new directory
RD
Internal Removes a directory
DEL
Internal Deletes a file
TREE
Internal Lists all of the directory and
subdirectory names on a specified
disk.
DELTREE Internal Deletes directory, subdirectory, files
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DOS Commands
Command Type
Function
SET
Internal
Displays the contents of the
environment variables
SET DIRCMD=0
MEM
External
Displays memory properties
COPY
External
Copies a file
TYPE
Internal
Displays the contents of a text file
CLS
External
Clear screen
ATTRIB
Internal
Displays file attributes
+/- a,r,h,s
CON
Internal
Console in conjunction with COPY,
write the contents of the screen to
a file.
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DOS Commands
Command
Type
Function
FDISK
External
Partitions fixed disks
TIME
Internal
Sets the System Time
DATE
Internal
Sets the System Date
CHKDSK
External
Displays the status of a disk
DISKCOPY
External
Copies one floppy to another
EDIT
Internal
Text Editor
REN
Internal
Rename a text file
PROMPT
Internal
Changes the appearance of the
DOS prompt.
C:\>PROMPT $P$G
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FDisk Command
FDISK is used to configure or display information about the
partitions on a hard disk. CAUTION: Using FDISK can modify or
delete partitions on a hard drive. If this happens all the data on
that partition is gone!
FDISK / [options]
OPTIONS:
•
•
•
•
/EXT Creates an Extended Partition.
/LOG Creates a Logical DOS Volume in the Extended Partition.
/MBR This switch can be used to repair a Master Boot Record that
has been corrupted or damaged.
/PRI Creates a Primary Partition.
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Format Command
Formats a disk for use with MS-Dos.
FORMAT drive: [/Options]
OPTIONS:
• /B Allocates space on the formatted disk for system files.
• /S Copies system files to the formatted disk
• /C Tests the clusters on a disk that are currently marked "bad." By default,
FORMAT does not retest the clusters; it simply leaves them marked "bad".
This will recheck them.
• /SELECT It unformats a disk and makes it a non-system disk.
• /V[:label] Specifies a volume label. If the /V switch is omitted, or label is not
specified, a prompt for a volume label is displayed after formatting is
completed. If a label is specified and more than one disk is formatted in a
session, all of the disks will be given the same volume label.
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Label Command
Allows you to change the name of the drive or disk.
LABEL [drive:] [label]
OPTIONS:
•
•
Drive The location of the disk to be named.
Label The new volume label.
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Config.sys File
The Config.sys allows you to load drivers such as HIMEM.sys
and any driver ending with .sys. To load device files in memory
type "DEVICEHIGH“.
•
REM in front of the line will prevent the line from loading the next
time you boot up the computer.
edit Config.sys
REM *****This is the Config.sys file*****
DEVICE=C:\WINDOWS\HIMEM.SYS
DOS=HIGH,UMB
DEVICE=C:\WINDOWS\EMM386.EXE NOEMS
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AutoExec.bat
It allows you to boot various programs and device drivers. The
Autoexec tells DOS were to find directories and files. Below is a
example of what the Autoexec.bat.
•
REM in front of the line will prevent the line from loading the next
time you boot up the computer.
edit Autoexec.bat
@echo off
REM *****This is the AutoExec.bat file*****
LH C:\WINDOWS\COMMAND\MSCDEX.EXE /D:MSCD0001
LH C:\MOUSE\MOUSE.EXE
CLS
•
CLS is to clear the screen after all the files is loaded.
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Optimizing at the DOS Level:
HIMEM.SYS
HIMEM.SYS is the device driver required by Dos to use
extended memory. The Device=Himem.sys line must come before
the Device=Emm386.exe and DOS=HIGH,UMB lines. The default
values for HIMEM.SYS are designed to work with most hardware.
Device= Himem.sys [/Options]
DOS=HIGH,UMB
OPTIONS:
• /A20Control:ON HIMEM always takes control of the A20 line (Default).
• /A20Control:OFF HIMEM only takes control of the A20 line if it is off when
Himem.sys loads.
• /EISA Specifies that HIMEM should allocate all available extended memory.
• /NOEISA Specifies that HIMEM should not do EISA scanning for extended
memory.
• /TestMem:ON Memory testing is undertaken at startup (Default).
• /TestMem:Of Memory testing is not undertaken at startup. This option will
slightly speed the startup process.
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Optimizing at the DOS Level:
Emm386
This allows you to extended the memory in DOS, without this
or any other extended memory manager your computer would
only have the basic 640kb. Although few programs these days
use expanded memory, EMM386 is still needed to allow access
to the upper memory area.
Device=Emm386 [options] [Parameters]
OPTIONS:
•
•
•
•
•
•
ON Activate on startup.
OFF Not activated at startup.
AUTO Not activated at startup but is automatically activated if any program calls for
it.
NOEMS Provides access to the upper memory area but does not provide any
expanded memory.
NoHi Emm386.sys remains entirely in conventional memory
H=handles How many handles EMM386 can use. Values range 2 through 255. The
default value is 64.
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Optimizing at the DOS Level:
Files
Specifies the number of files that MS-DOS can access at one
time.
FILES=x
OPTIONS:
• x The number of files that can be accessed at one time. x can be from 8 to
255 (default is 8) A value of 30 has been recommended as a good general
purpose figure.
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Optimizing at the DOS Level:
Buffers
Used to specify the number of "disk buffers" and "secondary
cache buffers" to be made available in memory. Buffers are
used to temporarily store information while it is being moved
between disk and memory. Secondary cache buffers act as
cache memory to hold unused parts of files in anticipation of
their use.
BUFFERS=n [,m]
OPTIONS:
• N Number of disk buffers to be allocated. n must be from 1 to 99 (default is
30)
• M Number of buffers in the secondary buffer cache. m must be from 0 to 8
(default is 0)
• The number of buffers should be set to 10 if SMARTDRV is being used and
20 if not. Using more than 10 buffers with SMARTDRV decreases efficiency,
and using more than 20 buffers without SMARTDRV uses more of the
system’s conventional memory area.
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Optimizing at the DOS Level:
Stacks
Sets up areas in memory called "Interrupt Stacks" to store
interrupts from hardware. This helps to prevent MS-Dos being
overwhelmed by multiple devices simultaneously demanding
processor action.
STACKS=n,s
OPTIONS:
• n The number of stacks. n can be from 8 to 64 or 0. The default is 9.
• s The size (in bytes) of each stack. s can be 32 to 512 or 0 (if n is 0). The
default is 256.
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Optimizing at the DOS Level:
SmartDrive
SMARTDrive is a disk-caching utility.
SMARTDRV [/Options]
Options:
• /X Disables write-behind caching for all drives.
• /U Do not load CD-ROM caching module.
• /F Writes cached data before command prompt returns (default).
• /N Doesn't write cached data before command prompt returns.
• /L Prevents SMARTDrive from loading itself into upper memory.
• /V Displays SMARTDrive status messages when loading.
• /Q Does not display status information.
• /S Displays additional information about SMARTDrive's status.
• Set the memory cache size for the SMARTDRV.EXE command
in the AUTOEXEC.BAT file to the largest size possible.
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Optimizing at the DOS Level:
RamDrive
Uses part of the computer's random-access memory (RAM)
to simulate a hard disk drive. RAM drives can be useful when
working with programs that do frequent disk read/write
operations.
Device=\DOS\RamDrive.sys [Options] [Parameters]
• DiskSize Specifies the size of the RAM drive in Kb. Valid values is from 4 to
32767 or max amount of memory available, whichever is less. (Default is
64).
• SectorSize Specifies SectorSize can be 128, 256, or 512 bytes (Default:
512). If a value is specified for SectorSize, DiskSize must also be specified.
• NumEntries Specifies the maximum number of files and directories you can
create in the RAM drive's root directory. It can be from 2 to 1024 entries
(Default is 64).
• /A Creates the RAM drive in expanded memory. You must enable
Expanded-memory manager EMM386 in the CONFIG.SYS.
• /E Creates the RAM drive in extended memory. You must enable extended
memory manager Himem.sys in the CONFIG.SYS.
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Optimizing at the DOS Level:
DriveSpace
Enables the loading of the real-mode DrvSpace driver
(DrvSpace.bin) into upper memory.
DeviceHigh=[Path]DrvSpace.sys /Move [/NoHMA] [/Low]
OPTIONS:
• /Low Prevents DrvSpace.sys from loading at the top of conventional
memory. The only occasion on which this switch would be required is if
some Dos program cannot work with DrvSpace located at the top of
conventional memory.
• /Move Moves DrvSpace.bin to its final location.
• /NoHMA Prevents DrvSpace.sys from moving DrvSpace.bin into the high
memory area (HMA).
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These activities are illustrated by the sample
CONFIG.SYS file:
Device=C:\DOS\HIMEM.SYS
DOS=HIGH,UMB
Device=C:\DOS\EMM386.EXE NOEMS
FILES=30
BUFFERS=15
STACKS=9,256
Device=C:\DOS\SMARTDRV.EXE /V
Device=C:\DOS\RAMDRIVE.SYS /A
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Adding DOSKEY
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Adding DOSKEY
Command used to either allow you to redo a particular command
or to repeat a command. DosKey is designed to assist in working
from the command line, by remembering previous commands, or
being able to record macros. DOSKEY allows you to use the
arrow keys to display previous commands.
DOSKEY [/Switches]
OPTIONS:
• /BUFSIZE:size Sets size of the buffer for macros and commands buffer
(default:512)
• /HISTORY Displays all commands stored in memory
• /KEYSIZE:size Sets size of keyboard type-ahead buffer (default:15).
• /LINE:size Sets maximum size of line edit buffer (default:128).
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DOSKEY Commands
 Esc
clears current command
 Ctrl + Left/Right cursor Moves the cursor back/forward one
word.
 Home/End Moves the cursor to beginning/end of line.
 Left/Right cursor Moves the cursor back/forward one
character.
 Page Up/Down Recalls the oldest/most recent command in the
buffer
 Up/Down cursor To scroll up (and back) through the list of
stored commands. Each press of the "up" key recalls the
previous command and displays it on the command line.
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Adding DOSKEY




Edit the AUTOEXEC.BAT file
At the end of the file add
DOSKEY.COM
Save and Exit
Restart
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Prompt Command
To change the command prompt. Allows you to choose the kind
of prompt you would like to see at DOS, the prompt is the "C:\>"
PROMPT [options]
OPTIONS:
•
•
•
•
•
•
•
•
•
•
•
$B | (pipe)
$D Current date
$G >(greater-than sign)
$H Backspace (erases previous character)
$L <(less-than sign)
$N Current drive
$P Current drive and path
$Q= (equal sign)
$T Current Time
$_ Carriage return and line feed
$$ $(dollar sign)
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Configuring the CD
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Configuring the CD



Create a directory on your C drive
named CDROM
MD C:\CDROM
Insert the driver disk
Copy the drive to the CDROM Directory
COPY A:\OAKCDROM.SYS
C:\CDROM
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Configuring the CD



Open the CONFIG.SYS file
Configure the CDROM driver
DEVICEHIGH=C:\CDROM\OAKC DRO
M.SYS /D:CD_DRIVE
Save and Exit
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Configuring the CD






Open the AUTOEXEC.BAT file
At the end of the file type:
LOADHIGH C:\DOS\MSCDEX.EXE
/D:CD_DRIVE
On the next line type:
LASTDRIVE=Z
Save and Exit
Restart the computer for changes to take
effect.
Watch for errors when starting.
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Adding Network Support
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Adding Network Support





Insert the Network Client 3.0 for MSDOS into our CD drive.
Type d:\
Type setup [Enter] [Enter]
Accept the default path of C:\NET
Select Network adapter not shown
on list below
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Adding Network Support



Set path to D:\PCM100 [Enter]
Select Linksys EtherFast … (PCM100)
Username: Your Name [Enter]
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Adding Network Support

Look at the Setup Page:



Change Names- configures your
user, computer, workgroup and
domain names.
Change Setup Options- specifies the
type of client you want to install.
Change Network Configurationsenables you to specify the driver for
your network card and protocol to
use.
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Adding Network Support

Select Change Names [Enter]





Username: Your Name
Computer Name: Cisco##
Workgroup name: Workgroup
Domain Name: CISCO
Select List names are correct
[Enter]
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Adding Network Support

Select Change Setup Options [Enter]





Redir Options: Full Redirector
Startup Options: Run Network Client
Logon Validation: Logon to Domain
Net Pop Hot Key: N
Select option are correct [Enter]
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Adding Network Support

Select Network config [Enter]



Select Add Protocol [Enter]
Select Microsoft TCP/IP [Enter]
Select Network config is correct
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Adding Network Support



Select The Listed options are correct [Enter]
The OEM Driver is located at D:\
When installation is complete, remove the CD,
insert the NIC card, plug in cable, and restart the
computer.
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Network Commands


Net start- loads the programs for logging on
to the network (AUTOEXEC.BAT was
configured by default to run this command at
startup).
Net stop- unload the client and disconnects.
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Network Commands


Net view \\computer_name- view a list
of shared resources on the specified
computer.
Net use E:
\\computer_name\share_nameassign a drive letter to a shared folder.
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Network Commands


Net use- view a list of the shared resources
currently connected.
Net use lpt1
\\computer_name\shared_printer_nameconnect your computer to a shared printer on
the server.
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MS-DOS External Commands
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PATH setup
Displays or sets a search path for executable files. Allowing you
to specify a directory to be used as a default directory that DOS
will look at when using a DOS command. When Dos searches
for a file, after first looking in the current directory, it looks
through the directories in the PATH statements.
PATH=path1;path2
•
When a number of paths are listed, they must be separated by
semicolons with NO spaces.
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Changing the PATH




Edit the AUTOEXEC.BAT file
Change the path to:
PATH C:\NET;C:\DOS
Save and Exit
Restart
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