Linux Advance Command

Linux Advance Command

Vi Replace

 cw – Vi replace a single word from the current cursor position. To replace a whole word, you put the cursor on the the first character of the word.
c$ – replace the current line but doesn’t extend to change the rest of a wrapped sentence on the screen
r – Vi Replace the character under the cursor
R – Replaced the text on the same line until Esc is pressed, but it doesn’t change text on the next line. Instead, it pushes to ahead of the current changes.

Vi Delete

 x – Deletes a single character under the cursor
X – Deletes a single character before the cursor
dw – Deletes a single word that’s currently under the cursor, from the cursor position onward.

Vi Delete Line

 dd – Vi delete line, regardless of the cursors position on the line
D – Deletes all text from the cursor position to the end of the line
dL – Deletes all text from the cursor position to the end of the screen
dG – Deletes all text from the cursor to the EOF
d^ – Deletes all text from the beginning of the line to the cursor

Vi Copy & Paste

 Commands for Vi copy & paste:
yy – Vi copy line – copies a line of text to the unnamed buffer
3yy – Copies 3 lines of text to the unnamed buffer
yw – Copies a word (under the cursor) to the unnamed buffer
3yw – Copies 3 words to the unnamed buffer
P – Pastes the contents 0f the unnamed buffer to the right of the cursor
p – Pastes the contents of the unnamed buffer to the left of the cursor

Vi Page Down

 Ctrl+F – Vi page down – Moves forward a page
Ctrl+D – Moves forward half a page

Vi Page Up

Ctrl+B – Vi page up – Moves back a page
Ctrl+U – Moves backward a half-page

Vi Save & Exit

 :q – Vi exit – this will close Vi
:wq – Vi save & exit
:w – Vi Save, write the file out to disk
: x – Vi exit, and prompts it you want to save on exit.
Shift+ZZ - Alternative way to save and exit Vi
:q! – Exits vi and discards and changes you made

:wq! – Vi Save and exit if you are root and do not have the write bit set for the file you are attempting to write.

# visudo

root ALL = (ALL) ALL

jons ALL = (ALL) ALL

shutdown command

#init 0

#halt

#shutdown –h now

#power0ff

#shutdown  -r 30

well be shutdown after 30minit

Reboot Command

#reboot

#shutdown –r

#init 6

VIM Editor

#   :s/string1/string2/g

replace all string1 to string2 All line in text file.

#   :s/string1/string2/gc

replace all string1 to string2 All line in text file. show line and word

# :set nu

Enable the line number

# :set nonu

Disable the line number

#cat a.txt > b.txt

#touch a.txt

for mack a new file.

#vim a.txt

for mack a new file

#wc –w a.txt

how mane line in the text file 

#head –n 1 a.txt

show the fist line in the text file

#cat –n a.txt

show the line number in the text file

RPM Command

#rpm –qa | wc –l

how to pakage install in the system

#rpm –qa nano

when the nano package   install in the system

#rpm –qc sandmail

show the  where  sendmail Configuration file

# rpm –qd sandmail

show the sandmail document file.

#rpm –ivh <pakag name>

for rpm pakage install

# rpm –ivh --forch <pakag name>

for rpm pakage forch install

#rpm –ivh –nodeps <pakage name >

for install rpm pakage without dependence file.

1.     nstall a local RPM:

rpm -ivh /path/to/my.rpm or: rpm -Uvh /path/to/my.rpm

2.     Remove a locally installed RPM:

rpm -e /path/to/my.rpm

3.     Upgrade/Update a locally installed RPM:

rpm -Uvh /path/to/my.rpm

4.     Find out what package a particular file belongs to:

rpm -qf /usr/bin/ssh

5.     Find useful information about a package:

rpm -qi openssh

6.     Find out when a package was installed:

rpm -q openssh --last

7.     List the dependencies of a package:

rpm -qR openssh

8.     List all gpg keys known by RPM on the system:

rpm -q gpg-pubkey --qf '%{name}-%{version}-%{release} --> %{summary}\n'

9.     Install an RPM from a website or anonymous FTP server:

rpm -ivh http://www.somewebsite.com/package.rpm

rpm -ivh ftp://ftp.somewebsite.com/package.rpm

10.   Repair and rebuild a corrupted RPM database:

rm -f /var/lib/rpm/__db* && rpm -vv --rebuilddb

11.   Find out what locations the files from a specific RPM were installed to:

rpm -ql openssh

12.   Make a text file of all the packages currently installed on the system sorted alphabetically:

rpm -qa | sort -d | uniq > all_packages.txt

samba-  2.0-     2.0.0-3.i386.  rpm

name         version     relese                        pakage name

Directory

 #cd ~

for go home directory

#cd ..

back one directory

#cd /

for go root directory

# last

login history all user

#last root

jest info about root user

#uptime

show the system uptime

#cat /proc/cpuinfo

for information on cpu

#free –t

system all information

#vmstat -s

show the virtual memory

#w

current all login user

#ps –A

Display the processes list

Change the time zone at system

#timeconfig

#rout or netstat –r

show all of the routing tables

#tracerout google.com

for trace the google site

#history

Show the before commands

#history –c

Remove the before command

#du –sh

Show the directory size

#top

Monitoring command

Network Command

 #ss –s

Display sockets summary

#ss –l

Display all open network port

#ss –t –a

Display tcp sockets

#ss –u –a

Display udp sockets

#ip –a

For about ip

#ip route

Show the getaway

#wall

Send massage in sash

Firewall Configuration

Iptables –l INPUT  -i eth0 –s 192.168.2.4 –j DROP                                    drop ip address

Iptables –l INPUT –s 192.168.2.0/24 –j DROP

 Iptables –l INPUT  -p tcp - -dport 80 –j DROP

Iptables –l INPUT  -i eth0 -p tcp –dport 80 –j DROP

Iptables –l INPUT  -p tcp –s 192.168.2.2  - - dport 80 –j DROP

User Account

#adduser jons

for add user

#passwd jons

for password on user

#passwd –l jons

lock account

#passwd –u jons

unlock account

#awk –F:’($==””){print}’/etc/shadow

verify account for empty password

#failog –r –u jons

for remote server a file upload

#scp –r /var/ root@hostname:/root/ssl

 Viewing live Bandwidth

#yum install iftop

#iftop –I eth0 –B

#iftop –I eth0 –n

#iftop –I eth0 –p –n

folder permission

#chmod –R 777 *.*

#chmod –R 776 /var/www/html/

all folder or file in directory permission 776

#chown –R user:group /var/www/html/

0 = no permission

1 = X  Execute only

2 = W Write only

3 = R Read only

# well

Send massage in ssh in command terminal

#lsof

for All port chack

#lsof –I tcp:80

for 80 port chack

#cksum jonsxm

for jonsxm file show size

#echo ‘wget url’ | at 1:00

if 1:00 time download the file then

#wget –limit-rate=20k url

if 20kbps speed to download the file

#wget –c url

#wget –r www.google.com

for full site download

#time cat

start stopwatch (ctrl+d to stop stopwatch)

#du –sch /var  /home

home and var how many size between two folder

#du –sh –exclude=’*.iso’ /home

all .iso file size in the home folder

#find / -name filename

search of total root folder

#locate filename

  search of total root folder

#find / cmin -5

find all file created or update in the five minit

ls  -l                         files and directories show current folder

ls  -la                       show file with (.) files

ls  -ls                        show files with size

ls  -ln                        show list numeric user/group ids instead of name

ls  -c                         show files listing columns

ls  --color =always   show files types as different colors 

Play Song

#play song.wav

play song

#play  *.wav

play all song

#mpg321  song.mp3

ISO CD Burn

#cdrecode  -v windows.iso

for burn cd

# cdrecode  -v speed=24  windows.iso

# cdrecode  -v –eject windows.iso

enject cd drive when burn in done

#restorecon –Rv  /var/www/html

restore the Default security

#mtr  www.google.com

no stop traceroute

#host www.google.com

remote server know for hostname & IP

#yum chack –update

chack for update list

#yum update

for update all package

 

#tar –xvf  file.tar

for unzip

#tar –cvf  file.tar  foldername

for tar

#ifup eth0

network card disable

#ifdown eth0

network card enable

#groupdel  groupname

delet groupname

#gpasswd  -a username  groupname

under user on groupname

#userdel  -r username

delete username

#cat /set/group

show group

#chfn  -f newname  oldname

for change username

#df –l

harddisk information

#rmdir foldername

#rm –r  foldername

delete folder

To create a tar.gz archive from a given folder you can use the following command 

#tar -zcvf tar-archive-name.tar.gz source-folder-name 

To extract a tar.gz compressed archive you can use the following command 

#tar -zxvf tar-archive-name.tar.gz 

How to Disable SSL?

---

sudo a2dismod ssl
sudo a2dissite default-ssl
sudo service apache2 restart

Network Masks

Short Form	Full Form	No. Machines	Comment
/8	255.0.0.0	16,777,215	Used to be called an `A-class'
/16	255.255.0.0	65,535	Used to be called an `B-class'
/17	255.255.128.0	32,767
/18	255.255.192.0	16,383
/19	255.255.224.0	8,191
/20	255.255.240.0	4,095
/21	255.255.248.0	2,047
/22	255.255.252.0	1,023
/23	255.255.254.0	511
/24	255.255.255.0	255	Used to be called a `C-class'
/25	255.255.255.128	127
/26	255.255.255.192	63
/27	255.255.255.224	31
/28	255.255.255.240	15
/29	255.255.255.248	7
/30	255.255.255.252	3

#hostame - Displays the hostname and/or FQDN of the system 

#uname -a - Displays the hostname and detailed kernel version 

#cat /etc/redhat-release - Displays the version of Linux installed Example: 

#cat /proc/cpuinfo - Displays information about the CPU(s) 

#df -h - Displays the partitions, their sizes details, and mount points 

#free - Displays detail about the system memory and usage 

#lsof - Displays all open files 

#lsof -nPi:22 - Displays any open files which use port 22 

#locate httpd.conf - Displays the full path to any file named httpd.conf 

#updatedb - Rebuilds index of files for search using the locate utility

Copy, Move, Delete

#cp file1.txt file2.txt - Copies file1.txt to file2.txt 

#mv old.txt new.txt - Renames a file called old.txt to new.txt 

#rm file1.txt - Deletes file1.txt 

#mkdir httpds - Creates a new directory called httpds 

#cp -R httpd httpds - Recursively copies all files from directory httpd to httpds 

#cp -PR httpd httpds - Recursively copies all files from directory httpd to httpds and retains all permission settings 

#rm -rf httpd - Recursively deletes folder httpd and all contents 

#chkconfig --list - Displays all services and their state (start or stop) at each runlevel

#chkconfig --level 35 httpd on - Sets httpd to start on runlevels 35 when machine is booted 

#service httpd start - Immediately starts Apache

File Attributes

#chown apache virtualhosts.txt - Changes ownership of the virtualhosts.txt file to user apache 

#chgrp apache virtualhosts.txt - Changes membership of the virtualhosts.txt file to group apache 

#chmod a+x sniffer.pl - Allows the sniffer.pl file to be executed

CHMOD

7 rwx read, write, execute 

6 rw- read, write 

5 r-x read, execute 

4 r-- read 

3 -wx write, execute 

2 -w- write 

1 --x execute 

0 --- no permissions

#chmod 777 passwords.txt - Allows read, write, and execute on the file passwords.txt to anyone 

#chmod 000 passwords.txt - Blocks read, write, and execute on the file passwords.txt to anyone

Yum

#yum update -y - Updates all packages without prompting 

#yum install iptraf - Installs a package named iptraf 

#yum whatprovides */iostat - Searches all repositories and returns RPMs that provide the program iostat 

#yum update samba - updates a package named samba

RPM

#rpm -q http - Displays the version of daemon http (apache) 

#rpm -qa | grep bind - Displays all packages installed with the word bind. Example: 

#rpm -qa | grep bind

bind-chroot-9.3.6-16.P1.el5 

system-config-bind-4.0.3-4.el5.centos 

bind-utils-9.3.6-16.P1.el5 

bind-9.3.6-16.P1.el5 

bind-libs-9.3.6-16.P1.el5 

ypbind-1.19-12.el5

#rpm -ivh proftpd - Interactively installs proftpd 

#rpm -Uvh proftpd - Interactive upgrades named proftpd 

#rpm -e proftpd - Removes package proftpd 

#rpm --rebuilddb - Rebuilds a corrupt RPM database

Compressed files

#unzip package.zip - Unzips the file package.zip 

#tar -zvxf stunnel.tar.gz - Decompressed a gzip file named stunnel.tar.gz

Networking

#ifup eth0 - Enables network interface eth0 

#ifdown eth0 - Disables network interface eth0 

#vi /etc/sysconfig/network-scripts/ifcfg-eth0 - Uses vi to edit network settings on eth0

IP tables

#service iptables status - Displays status of iptables (running or not) 

#iptables -L - Displays ruleset of iptables 

#iptables -I INPUT -p tcp -m tcp -s 192.168.15.254/26 --dport 22 -j ACCEPT - Accepts incoming SSH connections from IP range 192.168.15.254/26 

#iptables -I INPUT -p tcp -m tcp -s 0.0.0.0/0 --dport 22 -j DROP - Blocks SSH connections from everywhere else 

#iptables -I INPUT -s "192.168.10.121" -j DROP - Drops all traffic from IP 192.168.10.121 

#iptables -D INPUT -s "192.168.10.121" -j DROP - Removes previously allied drop all from IP 192.168.10.121 

#iptables -I INPUT -s "192.168.10.0/24" -j DROP - Drops all traffic from IP range 192.168.10.0/24 

#iptables -A INPUT -p tcp --dport 25 -j DROP - Blocks all traffic to TCP port 25 

#iptables -A INPUT -p tcp --dport 25 -j ACCEPT - Allows all traffic to TCP port 25 

#iptables -A INPUT -p udp --dport 53 -j DROP - Blocks all traffic to UDP port 53 

#/etc/init.d/iptables save - Saves all IPtables rules and re-applies them after a reboot

Processes

#ps ax - Displays all running processes 

#ps aux - Displays all running processes including CPU and memory usage of each 

#ps ax | wc -l - Displays the total number of processes 

#top - Interactive process manager which allows sorting by criteria

Logs

#tail -f /var/log/messages - Displays the most current entries to the messages log in real-time 

#tail -50 /var/log/messages - Displays the last 50 lines of the messages log 

#head -50 /var/log/messages - Displays the first 50 lines of the messages log 

#cat /var/log/messages - Displays the entire messages log 

#cat /var/log/messages | grep "FTP session opened" - Displays any entries in the messages log that contain the ext FTP session opened 

#cat /var/log/messages | grep "FTP session opened" > log2.txt - Writes any entries in the messages log that contain the ext FTP session opened to a file named log2.txt

Paths to Common Files

Bind (named)

/var/named - Bind zone files (non chrooted) 

/etc/named.conf - Bind configuration file (non chrooted) 

/var/named/chroot/var/named - Bind zone files (chrooted) 

/var/named/chroot/etc/named.conf - Bind configuration file (chrooted)

Apache (httpd)

/etc/httpd/conf/httpd.conf - Main apache configuration file 

/var/www/html - Default directory for serving pages 

/var/log/httpd/ - Default location for logs (access and error)

Networking

/etc/hosts - System hosts file 

/etc/resolv.conf - DNS lookup configuration file 

/etc/sysconfig/network - Network/hostname configuration file 

/etc/selinux - SELinux configuration file 

/etc/sysconfig/network-scripts/ - Default location of a network setting file 

/etc/sysconfig/iptables - Default iptables policy configuration file 

/etc/sysconfig/iptables-config - Default iptables daemon configuration file