Base Band

New posts about Base Band.

Earth Station

New posts about Earth Station.

Computer Networking

All posts about Computer Networking.

Product Review

New product reviews.

Command used in Linux. part -4

# systemctl --- For managing services on a RHEL 7 system

# service --- Run a system V init script

# tar ---- To compress files and folders

# touch --- To create or update a file.

# type --- to know any specific command is shell builtin or not

# !! --- To repeats the last command

# uptime –V --- It shows the version

# uname --- Print system information

# users --- Show the user name

# uptime --- Display the current uptime

# umount --- To unmounts the drive

# vgcreate --- To create volume group

# whatis --- Describe briefly of any command

# which --- determine the position of any command

# whoami --- To know the user name

Command used in Linux. part -3

# man --- man stands for manual. It is the command reference book of linux

# makewhatis --- to update database 

# mkdir --- To create directory

# more --- It allows quickly view file and shows details in percentage

# mount --- To mount a drive

# partprobe --- command is used to inform the operating system of partition table 

# passwd --- To set or modify password of the user

# pvcreate --- To create physical volume

# ps --- To find process ID

# pwd --- To know the present working directory

# parted — A disk partition manipulation program

# pr –x --- Divides the file into x columns

# pr –h --- Assigns a header to the file

# pr –n --- Denote the file with the number

# poweroff = init 0

# rm --- To remove file or directory without prompting for confirmation

# rm –rf --- To remove file or directory if it has content

# rm –r --- Delete directory

# rm –I file1 file2 --- prompt to the user to delete every file

# reboot = init 6

# reset --- Reset the terminal

# runlevel --- Print previous and current Sysv run level

# rm –f --- Forcely remove file

# rmdir --- To remove the emptey directory

# su --- To switcher user

# sudo --- Allow regular user to run program with the security privileges of super user 
or root.

# shutdown –h now --- Shutdown the system now and do not reboot.

# service --- It call script located /etc/init.d directory

# ssh --- To login into remote host securely

# sftp --- To connect remote ftp host

Command used in Linux. part -2

# ip addr show --- To show IP  address

# ip addr add --- To add IP address

# ip addr del --- To delete IP address

# sudo --- Offers another approach to giving users administrative access.

# ip link set dev eth1 up --- To make the state of device eth1 up

# ip link set dev eth1 down --- To make the state of device eth1 down

# ip route show ---- To check the routing table information

# ip route del --- To removed assigned static routing

# kill --- To terminate process

# last --- Can watch user’s activity in the system

# lvcreate --- To create logical volume

# ls –l test --- To show the permission of only test file.

# ls –l /tmp --- List files under directory /tmp

# ls --- To show file or directory under the current directory.

# ls –R --- To show subdirectories  and all.

# ls –a --- To show hidden file

# ls –r --- Show files and directories in reverse order

# ls –ltr --- Show latest modification file or directory date as last

# ls –version --- Show the version of ls command

# ls –l --- To show the file and directory under the current directory in details ones.

# less --- It allows quickly view file

Command used in Linux. part -1

# adduser or useradd --- To add new user

# cd.. --- To go back one state

# cd / --- To go under the root

# cd --- To change directory

# cd ~ --- To go home directory

# cd ~ <user_name> --- go to user home directory

# cd - ___ go to previous working directory

# cp --- Copy a file from one location to another

# cal --- Show the calendar of the month

# cat --- To show a specific file on the screen.

# chkconfig --- Updates and queries run level information for system services

# clear --- To delete all the previous content of the shell. Same command is CTRL –l

# crontab –l --- List schedule jobs for current user

# crontab -e --- create a new crontab

# crontab -r --- Remove a cron table and cancel all schedule jobs

# cp -p --- To copy file from source to destination preserving same mood

# cp –i --- To be prompted before overwrite it

# date --- To show the current date and time

# df –h --- To show the partition status

# df –hT --- To show the partition status details

# echo --- Display text on the screen. Mostly used when writing shell command.

# exit --- Logout from the current session.

# free --- To shows free, total and swap memory information in bytes

# free –t --- To shows total memory used and available to use in bytes

# find --- To search files, strings and directories

# ftp --- To connect remote ftp host

# fdisk --- To know the partition of the current directory

# fdisk –l --- To show the details of partition of the current directory

# groups --- Show groups you are in

# grep <search_string> ---- Can find a specific string by this command

# grep –w ---- Shows all the lines that do not matched the searched string

# grep –c ---- Display only the count of matching lines

# grep –m --- Show the matching line and its number

# grep –i --- Match both (upper and lower case)

# grep –l --- Shows just the name of the file with the string

# head --- Display the first few lines of the text file.

# history --- To show all previous command

What does it mean in Linux ? Part - 1

In Linux the syntax has special meaning. Some of them are given bellow:

# cat <file1> <file2> > <new file> --- To combine file1 and file2 into new file.

# cat <file> --- It show the content of the file . Cat command can be displayed only the text file.

# chown guru99 : guru99 test --- change user as guru99 and group as guru99 of test file at a time.

# rm <file> --- Delete file

# cat > <file> ---- Write content into this file. Then press Ctrl + D to come back to shell.

# chgrp root test --- Change groups as root of test file.

# chmod g+x test --- Add execute permission to the group for the test file.

# cp <source_file> <destination_file> --- Copy source file to destination file

# ls <ABC> <DEF> --- List the content of both directories <ABC> <DEF>

# ls ABC DEF > dirlist --- Standard output redirection to the dirlist

# cat sample | grep a --- Look for line containing the character a

# cat sample | grep ^a --- Look for the line which start with a.

# cat sample | grep t$ --- Look for the line which end with character.

# cat sample | grep –E p\{2} --- Look for the line where character  p appearing exactly two times one after the other. [as for example: apple]

# cat sample | grep “a\+ t” --- Look line where character a precede character t.

# ls ABC DEF > dirlist 2>&1 --- It will redirect error output to the standard output and standard output to the dirlist.

# echo {aaa, bbb, ccc, ddd} --- aaa bbb ccc ddd

# echo {a . . z} --- a b c d e f g h I j k l m n o p q r s t u v w x y z

# echo {1 . . 11} --- 1 2 3 4 5 6 7 8 9 10 11

# echo a{0 . . 9}b --- a0b a1b a2b a3b a4b a5b a6b a7b a8b a9b a10b

# lp –nc <filename>  --- Prints c copies of file

# lpr c <filename> --- Prints c copies of file

# lp –d <printer_name> <file_name> --- specify name of the printer

# lp –p <printer_name> <file_name> --- Specify name of the printer

# ps <PID_number> --- To know the status of the specific process

# pidof <process_name> --- To know the pid of the specific process

# mailx <address> <body> --- Command to send mail

# mv <source_file> <destination_file> --- Move (cut) source file to destination file 

# Chmod o=rwx test --- Set permission for other on tset file

# chmod u-r test --- Remove read permission to the user for the test file.

# mkdir /temp/music --- Create music directory under temp directory.

# rmdir <directory name> --- Remove directory and sub-directory of the directory.

# mkdir <dir1> <dir2> <dir3> --- Create multiple directory at a time.

# chmod <permission> <filename> --- This mean Change Mode. This command is used is set permission (read, write and execute) on a file/directory for the owner, group and the world. [Exmp. Chmod 764 test]

# mv <directoryname> <newdirectoryname> --- Move a file to a new location or rename it. Need to be superuser.

Abbreviation related with Linux

Some term related with Linux

ACL --- Access Control List

ANTP --- All Numeric TCP Protocol

BIOS --- Basic Input output System

BIND --- Berkeley Internet Domain Name

CIFS --- Common Internet File System

Crond --- Cron Demon

CUPS --- Common Unix Printing System

DAT --- Digital Audio Tape

DDS --- Digital Data Storage

DHCP --- Dynamic Host Configuration Protocol

DNAT --- Destination NAT

FHS --- Filesystem Hierarchy Standard 

FQDN --- Fully Qualified Domain Name

GNU --- GNU is not Linux

GPL --- General Public Licence

GRUB --- Grand Unified Boot loader

IANA ---- Internet Assigned Numbers Authority

ICANN --- Internet Corporation for Assigned Names and Numbers

IETF --- Internet Engineering Task Force 

IRR --- Internet Resources Register-er

ITP --- Internet Rime Protocol

KVM --- Kernel-base Virtualization Module

LDAP --- Lightway Directory Access Protocol

LDIF --- LDAP Data Interchange File

LPD --- Line Print Daemon

LUKS --- Linux Unified Key Setup

LV --- Logical Volume

LVM --- Logical Volume Management

MAC --- Mandatory Access Control

MBR --- Master Boot Recoder

MDA --- Mail Delivery Agent

MTA --- Mail Transfer Agent

MUA --- Mail User Agent

NAT --- Network Address Translation

NetStat --- Network Statistic

NFS --- Network File Systems

NSA --- National Security Agency

NSS --- Name Service Switch

NTP --- Network Time Protocol

PAM --- Pluggable Authentication Modules

PID --- Process Identification

POST --- Power On Self Test

PV --- Physical Volume

PXE --- Pre-boot Execution Environment

RADIUS --- Remote Authentication Dial In User Service

RAID --- Redundant Array of Independent Disk

RHEL --- Redhat Enterprise Linux

RPM --- Redhat Package Manager

SAN --- Storage Area Network

SCSI --- Small Computer System Interface

SELinux --- Security Enhanced Linux

SMB --- System Message Block

SNAT --- Source NAT

SWAT -- Samba Web Administration Tools

SSH --- Secure Shell

TFTP --- Trivial File Transfer Protocol

UUCP --- Unix to Unix Copy

VG --- Volume Group

VNC --- Virtual Network Computing

YUM --- Yellow-dog Update Modifier