Common DOS Commands Additional information. Important DOS Concepts Common DOS Commands Why format a disk? Partitioning and Formatting disks Structure

Common DOS Commands

Additional information

Important DOS ConceptsCommon DOS Commands

Why format a disk?Partitioning and Formatting disksStructure of a disk

Physical structure of a diskLogical structure of a diskFile System Formats

Backing up FilesOverwriting FilesMaking Exact Copies of Files

Chapter 2 adds (42 slides) CTEC 110 2

Important DOS CommandsCommon DOS Commands

FORMAT LABEL VOL MOVE DIR CHKDSK TYPE COPY DEL RENAME


Why Format a Disk?

Disks used for:Permanent storage of data and programsDistributing data from one computer to anotherMaking copies

Formatting (initializing) the disk:Process of preparing disk so that it is compatible

with an operating systemAll disks (including hard disks) can be formatted.All information on disk will be erased

CTEC 110 4Chapter 2 adds (42 slides)

Partitioning and Formatting Disks

Hard disks must be: Partitioned Formatted with file system

Types of disk storage configuration: Basic disks Dynamic disks


Partitioning and Formatting Disks

Windows supports four file systems:NTFSPlus three FAT file systems

– FAT12– FAT16– FAT32


Structure of a Disk Two parts to formatting a disk:

Low-level (physical) formatting High level (logical) formatting

Low-level (physical) formatting: Sequentially numbers tracks and sectors Identifies each track and sector Disk is physically prepared to hold data

High-level (logical) formatting: Determines how OS uses a disk Builds structure to keep track of location of files Done so files can be stored and retrieved.


Structure of a Disk

Windows will monitor the status of all

data sectors

One or more sectors are combined into logical units called clusters or allocation units


Physical StructureTrack, Sector, & Cluster


Logical StructureMaster Boot Record & Boot SectorMaster boot record (MBR):

First part of hard diskLocates bootable partition of hard disk and gives

control over to it

Boot sector:First sector on logical driveHas table of drive’s characteristicsHas bootstrap loader programAll disks (including non-system disks) have a

boot sector.


Logical Structure


Logical StructureFAT and the Root Directory

FAT tracks “where” data is on the diskFAT – File Allocation Table

A table that tracks the physical clusters

Root directory tracks “what” is on the disk.Root Directory:

A table that tracks file information


File System FormatsFAT16, VFAT & FAT32

FAT essential for:Managing dataFollowing trail of clusters that make up a file

VFAT maintainsbackwards compatibility andaccommodates long file names

FAT32:Enhancement of FAT file system Introduced to overcome limitations of VFAT


FAT32

FAT32:Movable Root Directory

• Can be located anywhere on hard disk

NOTE: For disk security, performance, and efficiency use the NTFS file system


NTFS

Advantages of NTFS: Secure file system Efficient storage of data Faster file access Better data recovery Can compress files/assign disk quotas Encryption of files


NTFS

NTFS: Uses FAT cluster scheme for allocating data.Has less overhead.


Master File Table (MFT)

Master File Table (MFT):

Database of all files in systemUsed by NTFS to track all files and directories

in a volumeDynamicMFT is different from FAT.


File System Format Notes

You can convert FAT to FAT32/NTFS

You CANNOT convert FAT32/NTFS to FAT

Make use of the NTFS file system for disk security, performance, and efficiency


Backing Up Files

Application programs can usually be reinstalled from original disks.

You may want to take snapshots or backup the configuration of your programs for quicker recovery

Always keep track of any special licensing tricks you need to do

19Chapter 2 adds (42 slides) CTEC 110

DOS has three ways to back up data files:

DISKCOPY – (floppy drives)COPYXCOPY


Backing Up Files

Develop a regular backup routine.You can use “tape backup”You can use writable CDsYou can use “external drives”


Backing Up Files

Notes on the Backup diskKeep currentHave two or moreCheck your backups with restore regularly

Some organizations need to recreate recordsNeed archival backupNeed transaction history


Backing Up Files

Do regular backups:Back up files that have changed or are new

Reasons for copying files:Copy files from one disk to anotherMaking changes on existing fileCreate backup copy of various data files


Backing Up Files

Overwriting Files

The file must have a unique name on same disk and subdirectory

Old data replaced by new dataOverwrite files on regular basis as you

want to backup filesWindows will inform the user that an

overwrite will occur


Concatenation is creating another file by combining the contents of two or more text (ASCII) files

Concatenation should never be done with program files, or with data files generated by programs

To avoid accidental concatenation of files, read all messages DOS displays on the screen

COPY FILE1 + FILE2 NEWFILECOPY *.TXT ALLFILES


Overwriting Files

Exact Copy of Files

You can have two files with identical contents on same disk

However there are some restrictions…For the same name

• Use different subdirectories

For the same subdirectory• Use different file names


A Review on Some Commands

CTEC 110 27

FORMAT formats driveLABEL labels driveVOL list volume label on driveCOPY copies filesXCOPY copies filesTYPE display the contents of filesDEL deletes filesREN rename filesMOVE move filesDATE set the dateTIME set the timeUNDELETE undelete a file

Chapter 2 adds (42 slides)

The FORMAT command

The FORMAT command syntax:FORMAT volume [/FS:file-system] [/V:label] [/Q] [/A:size] [/C] [/X] [/P:passes] [/S:state]

FORMAT volume [/V:label] [/Q] [/F:size] [/P:passes]

FORMAT volume [/V:label] [/Q] [/T:tracks /N:sectors] [/P:passes]

FORMAT volume [/V:label] [/Q] [/P:passes]

FORMAT volume [/Q]


Use /V: switch for the volume label• No spaces between the colon and label

Use /Q switch for a quick format• Fast way to clear previously formatted disks• Works like the usual FORMAT command• Skips low level formatting• Clears the FAT and root tables• Does not check for bad sectors

Examples: FORMAT A: /V:FLOPPY1 FORMAT C: /Q FORMAT Z: /FS:FAT FORMAT U: /FS:FAT32


The FORMAT command

The LABEL Command

The LABEL command syntax:LABEL [drive:] [label]

Creates, changes or deletes the volume label of a disk

Example:LABEL A: OLDNAMELABEL A: NEWNAMELABEL A:

Input volume label - Up to 11 characters.Press ENTER only to delete label.


The VOL Command

The VOL command syntax:VOL [drive:]

Displays the disk volume label, if any

Example:VOL Z:

Volume in drive Z is USB_DISK_02Volume Serial Number is 64B8-54F3


The COPY Command

The COPY command syntax:COPY [/D] [/V] [/N] [/Y | /-Y] [/Z] [/L] [/A | /B ] source [/A | /B] [+ source [/A | /B] [+ ...]] [destination [/A | /B]]

Copies one or more files to another locationCan be used to combine file contents

Examples:copy c:\Windows\System32\cmd.exe c:\


The XCOPY Command

The XCOPY command syntax:XCOPY source [destination] [/A | /M] [/D[:date]] [/P] [/S [/E]] [/V] [/W]

[/C] [/I] [/Q] [/F] [/L] [/G] [/H] [/R] [/T] [/U]

[/K] [/N] [/O] [/X] [/Y] [/-Y] [/Z] [/B]

[/EXCLUDE:file1[+file2][+file3]...]

Has the capability of moving files, directories, and even whole drives from one location to anotherThe /S switch copies subdirectories and filesThe /E switch copies empty subdirectories

Examples:XCOPY c: a: /sXCOPY n:\*.* o:\ /e


The TYPE Command

The TYPE command syntax:TYPE [drive:] [path] filename

Internal commandOpens/displays contents of file on screenMust be a text/ASCII file for the display to be meaningful and readable

Example:TYPE z:\ctec110\breakusb.batTYPE o:\name.bat


The DEL Command The DEL command syntax:

DEL [/P] [/F] [/S] [/Q] [/A [[:] attributes]] [drive:] [path] filenameERASE [/P] [/F] [/S] [/Q] [/A [[:] attributes]] [drive:] [path] filename

Used to remove files from the disk Files are generally not recoverable The /P switch will ask to confirm deletion The /S switch will delete files in the subdirectories

Examples: DEL TEST.TXT DEL /p c:\Part* DEL /s p:\*.* (Directories will require confirmation)


The RENAME command

The RENAME command syntax:RENAME [drive:][path]filename1 filename2REN [drive:][path]filename1 filename2

Renames a file or filesYou cannot specify a new drive or path for your destination file

Examples:REN test testingREN testing test


The MOVE command

The MOVE command syntax:MOVE [/Y | /-Y] [drive:][path]filename1[,...] destinationMOVE [/Y | /-Y] [drive:][path]dirname1 dirname2

Can be used to rename a file or directory

Examples:move c:\windows\web c:\web2move c:\web2 c:\web3

Chapter 2 adds (42 slides) 37CTEC 110

There are some restrictions…

When moving group of files you cannot change the names

When moving an individual file/subdirectory you can change the name

You can move files/directories from one directory to another and from one drive to another


The MOVE command

The DATE command The DATE command syntax:

DATE [/T | date]

Displays or sets the dateRequires Administrator rights to changeType DATE without parameters to display the current date setting and to prompt for a new one

• Press ENTER to keep the same dateUse /T switch to skip the prompting for a new date

Examples:DATEDATE /TDATE 05-22-13 (Set the date to May 22nd, 2013)DATE 05.22.13DATE 05/22/13


The TIME command The TIME command syntax:

TIME [/T | time]

Displays or sets the system timeRequires Administrator rights to changeType TIME with no parameters to display the current time setting and a prompt for a new one

• Press ENTER to keep the same timeUse /T switch to skip the prompting for a new time

Examples:TIME TIME /TTIME 15:22 (Set the time to 3:22 pm)


The UNDELETE command The UNDELETE command syntax:

UNDELETE [d:][path][filename] [/DT|/DS|/DOS]UNDELETE [/list|/all|/purge[d:]|/status|/load|/U|/S[d:]|/Td:[-entries]]

Has been removed from current Windows OS versionsRestores files deleted with the DELETE commandRemoves the first character of the fileRequires user to supply first character of the file upon undelete

Examples:UNDELETE \letters\*.* /all

• (Recover all files in the letters directory)

UNDELETE /dt • (Recover files in current directory using the delete-tracking file)


END of Addition Information

HOMEWORK

Lab 2DOS Quiz 2


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Common DOS Commands Additional information. Important DOS Concepts Common DOS Commands Why format a disk? Partitioning and Formatting disks Structure