learn gnu linux in tamil part 2

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2 /GNU Linux - - 2

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This work is licensed under a - 3.0 Creative Commons Attribution ShareAlike Unported License.

3/ GNU Linux .

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1...................................................................................................................................9 Linux - .............................................................................9

2.................................................................................................................................15-Users ........................................................................................................15

sudo command.............................................................................................................15 adduser command.......................................................................................................16

su command.................................................................................................................17 -user sudo .............................................17

chown command..........................................................................................................19 chgrp command...........................................................................................................20

owner -group .......................................................20 userdel Command........................................................................................................21 Groups ...........................................................................................................................23

/ / :etc shadow file ......................................................................................................27 3.................................................................................................................................29

Disk Management............................................................................................................29-Partition :..........................................................................................29

-fdisk :........................................................................................................30 4................................................................................................................................36

Mount Unmount...................................................................................................36-Mount :........................................................................................36

Unmount :....................................................................................................37/ /etc fstab..................................................................................................................37

Filesystem :......................................................................................................38 :Mount Options .........................................................................................................38

-file mount :.......................................................................................39 -file system repair :.................................................................................41

5.................................................................................................................................42 Process Management......................................................................................................42

ps command.................................................................................................................42 pstree command..........................................................................................................42

top command................................................................................................................43 Kill command................................................................................................................44

6.................................................................................................................................45 :.............................................................45

:.....................................................................................45:repositories ..............................................................................................................45

-repo ...................................................................................46-Source :........................................................................................46

:..................................................................................46 :..........................................................................................47 - :upgrade ................................................................................................48

6 :...........................................................................................................48 :.......................................................................48

Deb file :..................................................................................................48 7.................................................................................................................................50

Shell Programming .............................................................................50 -Shell Script ........................................................................................50 -Shell Script .............................................................................................51

Variables........................................................................................................................51 Global Variables............................................................................................................51

Local Variables..............................................................................................................52 -local variable :......................................................................52

-Local variables -Global variables .................................................53 Special Variables..........................................................................................................54

8.............................................................................................................................55 - 2Shell Script ....................................................................................................................55

# Hash .........................................................................................55 Escape Mechanism .....................................................................................................55

Command substitution................................................................................................56 Positional Parameters..................................................................................................57

File descriptors.............................................................................................................58 Shift Command.............................................................................................................61

exit Command..........................................................................................................61 Numerical Comparisons..............................................................................................61 & Arithmetic Operators Expressions........................................................................62 Conditional Operators.................................................................................................63

9.................................................................................................................................64 3Shell Scripting ............................................................................................................64

Programming language Constructs..............................................................................64 If Statement..................................................................................................................64

case Statement............................................................................................................65 for Loop..........................................................................................................................67

while Loop......................................................................................................................69 until Loop.......................................................................................................................70

Functions........................................................................................................................72 10...............................................................................................................................74

Job Scheduling..................................................................................................................74 at command..................................................................................................................74

crontab ..........................................................................................................................74 11...............................................................................................................................77

Rsync backup .........................................................................................77 ;......................................................................................................77

.....................................................................................................................85.......................................................................................................................85........................................................................................................................85.............................................................................................................86 ........................................................................................................86

7 30, 2013 , .

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9 1

Linux -

, Linux . .

Linux 20- 70- . 1969- & AT T -subsidiary Bell

Laboratories Unix . -unix Linux .

Linux . GNU Minix .

GNU

1983- Richard M Stallman GNU .

-Cambridge Massachusetts Institute of Technology Artificial

Intelligence .

Stallman . -source code . .

&AT T -unix $40,000 .

" -unix source-code "

. . -Stallman . source code -source code

10

. -Stallman . .

1983- Stallman GNU. .

Stallman :

========, 27, 1983 12:35:59 EST

( ) GNU GNU is Not Unix -Unix compatible software system . , , .

GNU kernel -C Programs -utilities . , , ,editor shell C Compiler

, linker assembler . ,text editor , , a YACC an Empire game spreadsheet -applications

. online -hardcopy documentation .

-GNU unix . -unix . .

========== .

GNU GNU is Not Unix . Unix . . -unix

-windows . , Stallman Manifest GNU ( GPL General Public License) .

-GPL () .

11

( #0)Freedom

, ( #1)Freedom

( #2)Freedom

-Program , -programs ( #3).Freedom

. . GPL . , .

1990- GNU components . Emacs

, , text editor Compiler gcc GNU C Compiler debugger gdb stallman .

compiler , . , compilers ++, C Pascal Fortran . GCC GNU Compiler

Collection .

-Richard Stallman 1990- -GNU System . -component kernel . -kernel ( GNU Hurd )

-Mach -set of server process implement . Mach Carnegie Mellon Utah micro kernel .

kernel .

12

:Minix

1990- -Intel Microprocessor , -Microsoft . Microsoft

desktop , server . Intel -Intel compatible processors , -unix

-workstations . -unix based system , versions

-Intel .

-Unix -processors ( : & ) eg SGI MIPS . -Unix

-Intel Processor OS . 1987- Andrew Tanenbaum Minix -OS

. -Netherlands , Amsterdam -Vrije University . -Minix -OS .

OS . C -Assembly language 12,000 .

-Tanenbaum " : " Operating Systems Design and Implementation Minix . Linus Torvalds

-Minix -Linux .

:Linux

1991- Linus Benedict Torvalds Finland, Intel-Processor Unix

-kernel . Minix -prototype .

-Minix -kernel GPL . Linus Torvalds -kernel Linux .

1991- 25-August , -Minix news group -Torvalds .

.

13

:

Minix !!!

. . GNU . . -Minix . -Minix . . .

(1.08) bash (1.40)-gcc port . .

@ . . torvalds kruuna helsinki fi .

================ .

Torvalds Freax / 0.11-kernel makefile -programs . Ari lemmke -FTP site -system load

-directory / / pub OS Linux . Linux -OS .

1991- Torvalds - .

-Torvalds .

1992- Linux - , .

-Torvalds . Torvalds . - Linux . Linux . Linux - GPL , Linux -versions

14

.

Linux . compile -distribution format .

Linux GNU / GNU Linux Distribution .

, Red Hat Caldera . Debian distribution . - , , X windows system KDE

GNOME -GUI -distributions .

Torvalds . 0.01-version acknowledgement

-copyrights . , GNU-license .

-Linux .

1992- February / -GNU Linux distributions floppy-disk

, -floppy disk .

linux . GNU / -GNU Linux .

-GCC Compiler linux . GPL . Torvalds version0.12- GPL .

/ GNU Linux / -GNU Linux . / GNU Linux .

15

2

-Users

-user management -commands .

root ?

-Ubuntu install -root account . -root disable ubuntu developers . -root . sudo -tool .

-sudo -root .

-Ubuntu install / / etc sudoers -file . sudo

-admin group .

sudo command

-sudo -root user command.

-root -sudo . -sudo , root user .

-root . -sudo . -adduser command .

16

adduser command

sudo -adduser command -user . .

$ adduser harini

, harini user .

users / / etc passwd . harini user .

$ cat /etc/passwd

password x . / / etc shadow -users encrypt -password . .

17

$ sudo cat /etc/shadow

su command

su switch user . su . logout login .

$ su harini

-user sudo

root user sudo , user --user sudo . -harini sudo

, / / -etc group -harini . .

18

nano -vi editor . -nano -file open .

-arrow mark key -sudo entry . -sudo entry -comma ' ' harini type + ctrl O . -file overwrite .

19

-harini sudo

chown command

-chown command -file -owner . -LKG file , user Nithya . Harini , -command .

$ chown harini LKG

20

chgrp command

-chgrp command -file -group . -LKG file , group Nithya . Harini , -command .

$ chgrp harini LKG

owner -group

chmod command owner -group .

$ chmod nithya:shrini LKG

21

-owner -nithya , -group -shrini . -colon -dot .

userdel Command

-userdel command -user .

$ userdel harini

:Password Policy

password . . password 4 , -entropy checks .

22

/ / . / - etc pam d common password -file .

password :

-user , -password . -password .

-password command .

$ sudo chage -l shrini

23

-command .

$ sudo chage shrini

-password .

- sudo chage l shrini .

Groups -groups command. groups

-groups .

24

$ cat /etc/group

-groups command.

$ groups shrini

-group commands .

$ sudo addgroup clg$ sudo delgroup clg

25

clg group , .

-group :

$ sudo delgroup --only-if-empty group

-user -group :

$ sudo usermod -G group -a user

User :

-user backup .

$ sudo deluser --backup-to /location/to/put/backup/user --remove-home user

-User

-user home directory $ sudo deluser --remove-home user

26

, user home directory -user ownership -file

$ sudo deluser --remove-all-files user

-Group

-user -Group .

$ id user

/ / etc passwd file

/ / etc passwd text file . -file . root .

system user human user .

/ / -etc passwd :

. -file : . 7 .

27

1. : username

2. : password . x . / / etc shadow -file .

3. ( ) : User id UID (user id ) . 0 -root . 1-999 -system user -human user .

4. ( ) : Group id GID , ( Primary group id/ / ) -etc group .

5. : User Id info . . , , . finger .

6. : home directory (home directory ). .

7. / : command shell login command shell / / . bin bash command .

$ less /etc/passwd

$ grep nithya /etc/passwd

/ / :etc shadow file

/ / -etc passwd . / / etc shadow -file .

encryption . root . : .

28

1. Username :

2. Password : ( encryption )

3. : 1, 1970last password change Jan

4. Minimum : . .

5. Maximum : . .

6. Warn :

7. Inactive : ,

8. expire :

5 md algorithm encryption .

29

3

Disk Management

Hard disk .

/ /dev sda : Primary Master/ /dev sdb : Primary slave/ /dev sdc : Secondary Master/ /dev sdd : Secondary slave

-hard disk / / dev sda .

partition .

/ / 1dev sda/ / 2dev sda/ / 3dev sda/ / 4dev sda...

4 primary partition . 4 extended , -logical partition .

fdisk , -partition .

: . root . , . , . .

-Partition : -partition

$ sudo fdisk-l

30

1. -disk -partition

$ sudo fdisk -l /dev/sda

-fdisk :

, partition . . m

# fdisk /dev/sda

The number of cylinders for this disk is set to 9729.There is nothing wrong with that, but this is larger than 1024,and could in certain setups cause problems with:1) software that runs at boot time (e.g., old versions of LILO)2) booting and partitioning software from other OSs (e.g., DOS FDISK, OS/2 FDISK)

Command (m for help): mCommand action a toggle a bootable flag b edit bsd disklabel c toggle the dos compatibility flag d delete a partition

31

l list known partition types m print this menu n add a new partition o create a new empty DOS partition table p print the partition table q quit without saving changes s create a new empty Sun disklabel t change a partition's system id u change display/entry units v verify the partition table w write table to disk and exit x extra functionality (experts only)

2. -partition

# fdisk /dev/sda


Command (m for help): p

Disk /dev/sda: 80.0 GB, 80026361856 bytes255 heads, 63 sectors/track, 9729 cylindersUnits = cylinders of 16065 * 512 = 8225280 bytesDisk identifier: 0xf6edf6ed

Device Boot Start End Blocks Id System/dev/sda1 1 1959 15735636 c W95 FAT32 (LBA)/dev/sda2 1960 5283 26700030 f W95 Ext'd (LBA)/dev/sda3 5284 6528 10000462+ 7 HPFS/NTFS/dev/sda4 6529 9729 25712032+ c W95 FAT32 (LBA)/dev/sda5 * 1960 2661 5638752 83 Linux/dev/sda6 2662 2904 1951866 83 Linux/dev/sda7 2905 3147 1951866 83 Linux/dev/sda8 3148 3264 939771 82 Linux swap / Solaris/dev/sda9 3265 5283 16217586 b W95 FAT32

Command (m for help): dPartition number (1-9): 8



Command (m for help): wThe partition table has been altered!

Calling ioctl() to re-read partition table.

32

WARNING: Re-reading the partition table failed with error 16: Device or resourcebusy.The kernel still uses the old table. The new table will be used atthe next reboot or after you run partprobe(8) or kpartx(8)Syncing disks.

3. -partition

-partition , cylinder , -partition () cylinder .

, p print .

# fdisk /dev/sda


Command (m for help): nFirst cylinder (2662-5283, default 2662):Using default value 2662Last cylinder, +cylinders or +size{K,M,G} (2662-3264, default 3264):Using default value 3264

w .

Command (m for help): w

The partition table has been altered!



mkfs format .

33

# mkfs.ext3 /dev/sda7

4. -boot flag -partition boot a . .

# fdisk /dev/sda




Device Boot Start End Blocks Id System/dev/sda1 1 1959 15735636 c W95 FAT32 (LBA)/dev/sda2 1960 5283 26700030 f W95 Ext'd (LBA)/dev/sda3 5284 6528 10000462+ 7 HPFS/NTFS/dev/sda4 6529 9729 25712032+ c W95 FAT32 (LBA)/dev/sda5 * 1960 2661 5638752 83 Linux/dev/sda6 3265 5283 16217586 b W95 FAT32/dev/sda7 2662 3264 4843566 83 Linux

Partition table entries are not in disk order

Command (m for help): aPartition number (1-7): 5



Device Boot Start End Blocks Id System/dev/sda1 1 1959 15735636 c W95 FAT32 (LBA)/dev/sda2 1960 5283 26700030 f W95 Ext'd (LBA)/dev/sda3 5284 6528 10000462+ 7 HPFS/NTFS/dev/sda4 6529 9729 25712032+ c W95 FAT32 (LBA)/dev/sda5 1960 2661 5638752 83 Linux/dev/sda6 3265 5283 16217586 b W95 FAT32/dev/sda7 2662 3264 4843566 83 Linux

34


Command (m for help):

5. -partition order

-logical partition , , . . Partition out of order Partition table

.entries are not in disk order

6, 7, 8 Sda sda sda . 6 sda , 7 sda . 9 sda , 6 sda . f .

.

$ fdisk /dev/sda




Device Boot Start End Blocks Id System/dev/sda1 1 1959 15735636 c W95 FAT32 (LBA)/dev/sda2 1960 5283 26700030 f W95 Ext'd (LBA)/dev/sda3 5284 6528 10000462+ 7 HPFS/NTFS/dev/sda4 6529 9729 25712032+ c W95 FAT32 (LBA)/dev/sda5 * 1960 2661 5638752 83 Linux/dev/sda6 3265 5283 16217586 b W95 FAT32/dev/sda7 2662 3264 4843566 83 Linux


Command (m for help): x

Expert command (m for help): fDone.

Expert command (m for help): wThe partition table has been altered!

35



36

4

Mount Unmount

P -artition .

file system . 3, 4, ext ext, ReiserFS Btrfs / .filesystems

Journalins Filesystem . index , file index . , , hard

-disk .

m kfs file system .

sudo mkfs.ext4 /dev/sda5sudo mkfs.reiserf5 /dev/sda6 file system mount .

mount -raw / device partition / folder .

Mount , , , disk partition Linux network share windows network share iso file / cd dvd folder .

-Mount :

root sudo .

1:

sudo mount /dev/sda5 /songs

/ / 5 dev sda / -songs mount . /ls songs /cd songs / / 5 dev sda -file .

37

2:

sudo mount -t iso9660 movie.iso /media/movie

. movie iso -ISO file / / media movie -folder mount .

-folder mount . mount point . mount -filesystem , mount .

Unmount :

mount filesystem unmount.

- root . mount file folder , unmount

.

sudo umount /media/movie

/ /etc fstab

boot -filesystem -mountpoint mount . / / etc fstab file .

6 column . filesystem .

38

Filesystem :

filesystem :

3/ 4 ext ext : / file system9660 iso : iso file

proc : proc virtual file system vfat : 16, 32 fat fat file system auto : filesystem

nts : network file systemsmbfs : network file system

:Mount Options

Mount - o , .

/ / -etc fstab .

noauto : boot mount . / cd dvd .

ro : - Read Only mount users : root (mount ) unmount

. user : , mount unmount

39

/ / -etc fstab 5 , column dump . , dump restore backup . filesystem 1 , / / cd dvd usb -removable media 0 .

6 -column - pass no . boot file system check .

/ root 1-boot mount -file system 0

-file system 2

-file mount :

iso file -file device mount .

1.44 MB file .

dd if=/dev/zero of=disk.img bs=1024 count=1400 = dd disk dump

= if input file = of output file = bs block size

= count count of dump operation

-file .

file system back level copy .

dd if=/dev/sdb1 of=usb.imgmount -o loop usb.img /mnt/disk

40

disk :

disk space :

df

-disk space , . Mount point .

df -h

- h human readable , MB GB .

-folder :

< >du foldername

-folder .

du -hdu -sh

41

-file system repair :

, , , filesystem .

- Hardware . .

< > < >fsck option device

sudo fsck /dev/sda5

.

sudo fsck -y -f /dev/sda5

- = y yes for questions- = f force

fdisk file system unmount .

42

5

Process Management

process . parent process child process . init process .

-process pid refer .

ps command

-ps command -process .

ps

ps ax, ps -aux, ps -ef, ps -l .

pstree command

-pstree command -process , parent process -child process

tree .

pstree

43

top command

- top command process -process . -output

real time monitoring .

$ top

44

Kill command

-process . -process -signal

$ kill 2180

-screenshot -terminal 2180 pid . 2180 kill , terminal .

killall

, program , kill .

45

6

:

, synaptic software center GUI , -command .

Apt

, , . , , , user interface module library translation . . dependancy .

Package management system , , .

Redhat -distribution yum , , debian ubuntu , APT Arch-linux pacman .

:

sudo apt-cache search [search term 1] [search term 2] [search term n]

:repositories, , , debian ubuntu centos suse distribution

package . repository .

-repository . , .

46

, -debian ubuntu / / / .etc apt sources list repository .

-repo

sudo add-apt-repository [repository name here]sudo add-apt-repository ppa:tualatrix/ppa

-Source : -repo repo .

sudo apt-get update

:

:

sudo apt-get install [package name 1] [package name 2] [package name n]

47

, -repository .

:

sudo apt-get remove [package name 1] [package name 2] [package name n]

48

configuration file directory purge .

sudo apt-get remove purge

- :upgrade

sudo apt-get upgrade ...

upgrade

sudo apt-get upgrade , , .

sudo apt-get -s upgrade , simulate .

:

-repo -deb file .

sudo apt-get clean

:

sudo dpkg list

, .

Deb file :

49

/ debian ubuntu packages deb . , .

sudo dpkg -i

50

7

Shell Programming

, -shell , -program .

-shell -programming language . -programming language

, programming constructs logical , conditional operators command, , substitution escape mechanisms positional parameters

-shell .

-Shell Script

-unix -commands . commands " "shell script.

, , , date ls uname echo -unix commands ' 1' example -file . .

1 example shell script . -script , -output .

51

-Shell Script

-shell script .

1: sh -unix command -script file -argument -shell script . .

1 example -shell script -unix commands -output .

2: chmod unix command file -execute permission -script file execute . .

Variables

-Unix , -variables , local variables global variable . .

Global Variables

Global Variables unix , . environment variables .

PATH -variable -directory . 1 PS -variable -shell prompt , HOME -variable -home directory .

$ ( ) dollar -variables , .

52

$ $PATH $ $PS1$ $HOME

Local Variables

-shell environment -variable local variable. -shell environment , . ' ' shell variables .

-local variable :

, a b 2 -variable -shell environment .

-variables echo . .

53

-variables -shell script , .

variables . local variables -shell environment . shell variables

-global variables , .

-environment shell variables set -command .$ set

-Local variables -Global variables

-local variable -global variable export command.

, a b 2 -local variable -global variable , -shell environment -export command .$ export a$ export b

54

-variables -shell script . .

Special Variables

Local variable global variable -unix -variable .

$# positional parameters .

$- -shell options ,$? execute -command exit . $$ -shell process .$! -background command process .$0 execute -command .$* -Positional parameters .

55

8

- Shell Script 2

# Hash

# type , type , execution .

shell script , # ,

-shell script .

. ec sh -file -comment , run .

-output -comment .

Escape Mechanism

. * ( ) Asterisk symbol echo .

56

-echo command *- . * -unix .special character

* , Unix. -character

-unix .

-special characters -character -unix , -character backslash

(\) .

* . escape mechanism .

Command substitution

. -unix command echo .

57

ls .

-ls command -backticks echo .

ls -command -output echo . command substitution .

Positional Parameters

-Shell script -command line -arguments . -shell script $1

-argument , $2 -argument , $3 -argument .

$0 -shell script , $* command-line -arguments .

$1,$2,$3 , -arguments -position , positional parameters .

. arguments sh -shell script .

58

. -arguments sh -command line -arguments .

arguments , -shell script positional-parameters -output .

File descriptors

File descriptors 0,1 2 , standard input standard output -standard error .

-shell script , commands , error messages ,

program .

59

-descriptors , error messages , -file ,

program .

man xyz command -error . -error descriptor 2-

-file .

$ man xyz 2> file2

man ls xyz , -command ls -output , -xyz -error . , -output -file , -error -file .

$ man ls xyz 1> opfile 2> errfile

60

output error -file -command .

$ man ls xyz > operrfile 2>&1

61

Shift Command

-shell script $1 $9 positional-parameters . ,

-shift command .

exit Command

-exit command -shell script . -shell script 0-, 1- .

Numerical Comparisons

-shell script . , 3 5 .

3 - 5 (3 eq 5 ( ) equals )

3 - 5 (3 ne 5 ( ) not equals )

3 - 5 (3-gt 5- ( ) greater than )

3 - 5 (3-lt 5- ( ) greater than )

3 - 5 (3-ge 5- ( ) greater than or equal to )

3 - 5 (3-le 5- ( ) greater than or equal to )

-command line .

$ [ 3 -eq 3 ] && echo true $ [ 3 -eq 5 ] && echo true $ [ 3 -lt 5 ] && echo true $ [ 3 -lt 2 ] && echo true

62

-command 3 - 3 eq true . 3 - 5 eq true . -commands .

& Arithmetic Operators Expressions

, , , +, -, *, / arithmetic operators . -shell script . .

$ expr 6 + 4$ expr 6 - 4$ expr 6 \* 4$ expr 6 / 4 * -operators , \ -escape operator .

, / -operator , , .

63

Conditional Operators

-commands -successful execution -failed execution -commands execute . && || conditional

execution operators .

&& -operator -successful execution ,|| -operator -failed execution

-commands execute .

$ grep Apple fruits && echo found || echo Not found$ grep Mango fruits && echo found || echo Not found

64

9

3Shell Scripting

Programming language Constructs

-Shell -programming language & , looping branching , operations on variables file creation argument passing

. -shell , -DOS -batch files .

If Statement

-If Construct -condition -set of commands execute .

:syntax

if (condition)then

commandselse

commandsfi

:

2. example sh -file -if statement , run .

65

fruits -file Apple if command.

fruits -file absolute path . -shell script absolute path -files .

case Statement

Case statement -option , -commands execute .

:syntax

case value in choice1) commands; ;choice2) commands; ; . . . esac

:

3. example sh -file -case statement , run .

66

options echo statement . read function

input , choice -variable .

case statement -choice variable 1 pwd-command , 2 -date , 3 -who command

execute . * 1,2,3 , " message echo

statement .

-input , output .

67

for Loop

-list -output .

:syntax

for in do

Commandsdone

:

4. example sh -file -for loop , run .

68

-seq 1 10 argument , 1 command 10 .

-command backticks -output -for loop -condition .

1 10 -loop statement execute , output .

69

.

while Loop

-while loop condition -loop -commands execute .

:syntax

while do

Commandsdone

70

:

5. example sh -file -while loop , run .

i -variable 1 assign . -while loop condition , i ,variable

5 -loop execute .

-loop i variable . -i 5- loop output .

until Loop

-until loop -while loop . until-loop condition -loop -commands

execute .

71

:syntax

until do

Commandsdone

:

6. example sh -file -until loop , run .

output .

72

Functions

-shell script function . -commands , logical -function .

-functions .

function input , parameter .

:Syntaxfunction_name () {commands}

:

. functions sh -file -function , run .

73

1 , 2 value value 2 -variables read function 2 . 2

(), add (), sub (), mul () div 4 functions.

-functions 2 1 value 2 value 2 variables -function

-parameter .

output .

74

10

Job Scheduling

-Shell -jobs schedule at crontab 2 commands . .

at command

/ command shell script execute schedule at command .

$ touch india | at 16.39

touch command 4:39 -PM india -file .

crontab

-Crontab / -command shell script , execute .

-crontab file . - crontab e -file open .

.

- minute (0 59 ) - hour (0 23 ) - day of month (1 31 ) - month (1 12 ) - day of week (0 6 ) (0= )Sunday

75

touch command 25- 4. 40 -crontab command .

$ crontab -e 40 16 25 * * touch trade (press)Esc:wq (press)Enter

40 , 16 ,

25 . *

, * .

-crontab schedule commands l -option . .

$ crontab -l

77

11

Rsync backup

. , .

rsync , , , .

;

: source file directory destination . , Source file directory . backup, .

: , ssh

- encryption - , .

:bandwidth , . ( ). compress , . ( ). extract bandwidth .

: . root .

:Syntaxrsync

source destination , network . , , IP hostname destination full path .

78

- 1; directory sync .

- zvr options .

$ rsync -zvr /var/opt/installation/inventory/ /root/tempbuilding file list ... donesva.xmlsvB.xml.sent 26385 bytes received 1098 bytes 54966.00 bytes/sectotal size is 44867 speedup is 1.63$

,

- = - z compress - = - v verbose - = - r recusrsive .

timestamp .

$ ls -l /var/opt/installation/inventory/sva.xml /root/temp/sva.xml-r--r--r-- 1 bin bin 949 Jun 18 2009 /var/opt/installation/inventory/sva.xml-r--r--r-- 1 root bin 949 Sep 2 2009 /root/temp/sva.xml

. .

2: metadata sync .

Rsync - a option sync .

- = a archive mode symbolic link

permissionstimestamp

, owner group

- a .

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$ rsync -azv /var/opt/installation/inventory/ /root/temp/building file list ... done./sva.xmlsvB.xml.sent 26499 bytes received 1104 bytes 55206.00 bytes/sectotal size is 44867 speedup is 1.63$

timestamp sync .

$ ls -l /var/opt/installation/inventory/sva.xml /root/temp/sva.xml-r--r--r-- 1 root bin 949 Jun 18 2009 /var/opt/installation/inventory/sva.xml-r--r--r-- 1 root bin 949 Jun 18 2009 /root/temp/sva.xml

3: -file rsync

$ rsync -v /var/lib/rpm/Pubkeys /root/temp/Pubkeys

sent 42 bytes received 12380 bytes 3549.14 bytes/sectotal size is 12288 speedup is 0.99

4: local remote sync

remote , , IP () , hostname destination directory path .

@username hostname: / / / / .full path to destination

remote (password ) rsync .

' ' Passwordless ssh , password , remote rsync .

$ rsync -avz /root/temp/ [email protected]:/home/shrini/temp/Password:building file list ... done./rpm/rpm/Basenamesrpm/Conflictname


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5: remote local rsync .,

= source remote = destination local

.

$ rsync -avz [email protected]:/var/lib/rpm /root/tempPassword:receiving file list ... donerpm/rpm/Basenames.sent 406 bytes received 15810230 bytes 2432405.54 bytes/sectotal size is 45305958 speedup is 2.87

6: remote shell

- e option remote shell . - e ssh encryption rsync .

$ rsync -avz -e ssh [email protected]:/var/lib/rpm /root/tempPassword:receiving file list ... donerpm/rpm/Basenames


7: -Destination , overwrite .

-destination File . rsync -source . - u option.

$ ls -l /root/temp/Basenamestotal 39088-rwxr-xr-x 1 root root 4096 Sep 2 11:35 Basenames

$ rsync -avzu [email protected]:/var/lib/rpm /root/tempPassword:receiving file list ... done

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rpm/


$ ls -lrttotal 39088-rwxr-xr-x 1 root root 4096 Sep 2 11:35 Basenames

8: -directory structure rsync

Directory Tree (File ) rsync - d .

$ rsync -v -d [email protected]:/var/lib/ .Password:receiving file list ... donelogrotate.statusCAM/YaST2/acpi/


9: Progress

-file rsync , . rsync . -- progress . rsnapshot .

$ rsync -avz --progress [email protected]:/var/lib/rpm/ /root/temp/Password:receiving file list ...19 files to consider./Basenames 5357568 100% 14.98MB/s 0:00:00 (xfer#1, to-check=17/19)Conflictname 12288 100% 35.09kB/s 0:00:00 (xfer#2, to-check=16/19)...sent 406 bytes received 15810211 bytes 2108082.27 bytes/sectotal size is 45305958 speedup is 2.87

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10: -Destination delete

-source file delete , -target delete . .

delete -- delete .

# Source and target are in sync. Now creating new file at the target.$ > new-file.txt

$ rsync -avz --delete [email protected]:/var/lib/rpm/ .Password:receiving file list ... donedeleting new-file.txt./


11: rsync

source file , target file rsync . -- existing . [/var/lib/rpm ]$ > new-file.txt

$ rsync -avz --existing [email protected]:/var/lib/rpm/ [email protected]'s password:receiving file list ... done./


12: / source destination

- i .

:Source$ ls -l /var/lib/rpm-rw-r--r-- 1 root root 5357568 2010-06-24 08:57 Basenames-rw-r--r-- 1 root root 12288 2008-05-28 22:03 Conflictname-rw-r--r-- 1 root root 1179648 2010-06-24 08:57 Dirnames

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:Destination$ ls -l /root/temp-rw-r--r-- 1 root root 12288 May 28 2008 Conflictname-rw-r--r-- 1 bin bin 1179648 Jun 24 05:27 Dirnames-rw-r--r-- 1 root root 0 Sep 3 06:39 Basenames

$ rsync -avzi [email protected]:/var/lib/rpm/ /root/temp/Password:receiving file list ... done>f.st.... Basenames.f....og. Dirnames


13:

-rsync , .

$ rsync -avz --include 'P*' --exclude '*' [email protected]:/var/lib/rpm/ /root/temp/Password:receiving file list ... done./PackagesProvidenameProvideversionPubkeys


14: file size limit

-- - max size option -file rsync .

$ rsync -avz --max-size='100K' [email protected]:/var/lib/rpm/ /root/temp/Password:receiving file list ... done./ConflictnameGroup

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InstalltidNameSha1headerSigmd5Triggername


15: -file sync

, source target file rsync file rsync - w .

network bandwidth . checksum , .

# rsync -avzW [email protected]:/var/lib/rpm/ /root/tempPassword:receiving file list ... done./BasenamesConflictnameDirnamesFilemd5sGroupInstalltidName


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/ - GNU Linux - 3

Basics of Networking Basic Network Settings

Domain Name Server Network File Server Dynamic Host Control Protocol

Printing Apache Web server

Ssh

.

http://kaniyam.com : http://bit.ly/kaniyamThis work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.GNU/Linux . 30, 2013 , . : . .. , , , ( ) : . , 2004- , . ( ) , ,- , . .. 100 (6500 ) . , " MySQL" 5000 .: http://jasanpictures.com 1Linux - 2Users- sudo commandadduser commandsu command user- sudo chown commandchgrp command owner group- userdel CommandGroups/etc/shadow file:

3Disk ManagementPartition- :fdisk- :

$ fdisk /dev/sdaThe number of cylinders for this disk is set to 9729.There is nothing wrong with that, but this is larger than 1024,and could in certain setups cause problems with:1) software that runs at boot time (e.g., old versions of LILO)2) booting and partitioning software from other OSs(e.g., DOS FDISK, OS/2 FDISK)Command (m for help): pDisk /dev/sda: 80.0 GB, 80026361856 bytes255 heads, 63 sectors/track, 9729 cylindersUnits = cylinders of 16065 * 512 = 8225280 bytesDisk identifier: 0xf6edf6edDevice Boot Start End Blocks Id System/dev/sda1 1 1959 15735636 c W95 FAT32 (LBA)/dev/sda2 1960 5283 26700030 f W95 Ext'd (LBA)/dev/sda3 5284 6528 10000462+ 7 HPFS/NTFS/dev/sda4 6529 9729 25712032+ c W95 FAT32 (LBA)/dev/sda5 * 1960 2661 5638752 83 Linux/dev/sda6 3265 5283 16217586 b W95 FAT32/dev/sda7 2662 3264 4843566 83 LinuxPartition table entries are not in disk orderCommand (m for help): xExpert command (m for help): fDone.Expert command (m for help): wThe partition table has been altered!Calling ioctl() to re-read partition table.WARNING: Re-reading the partition table failed with error 16: Device or resource busy.The kernel still uses the old table. The new table will be used atthe next reboot or after you run partprobe(8) or kpartx(8)Syncing disks. 4Mount UnmountMount- :Unmount :/etc/fstabFilesystem :Mount Options: file- mount :file system- repair :

5Process Managementps commandpstree commandtop commandKill command

6 : :repositories: repo- Source- : : : - upgrade: : :Deb file :

7Shell Programming Shell Script- Shell Script- VariablesGlobal VariablesLocal Variables local variable - :

Local variables- Global variables- Special Variables 8

Shell Script- 2Hash # Escape MechanismCommand substitutionPositional ParametersFile descriptorsShift Commandexit Command

Numerical ComparisonsArithmetic Operators & ExpressionsConditional Operators

9Shell Scripting 3Programming language ConstructsIf Statementcase Statementfor Loopwhile Loopuntil LoopFunctions

10Job Schedulingat commandcrontab

11Rsync backup ;

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