Ethical Hacking and Penetration Testing Guide

Some Unforgettable Basics
Changing the Password
We would need to issue the following command in order to change the password of our Linux box. 
Generally, it’s a good practice to change the default password to prevent unscrupulous people from 
getting into the network. This is the reason I have kept this command at the top of the basics list.
passwd
Clearing the Screen
In Windows command prompt we use “cls”; inside Linux BackTrack we use the 
clear
command.
Listing the Contents of a Directory
ls
ls is used for listing the contents in a directory, the –l parameter can also be used for listing the 
permissions of the current directory.
Displaying Contents of a Specific Directory
ls/pentest/enumeration
It is used to list the contents of a specific directory. Issuing this command generates a list of the 
contents of the 
/pentest/enumeration
directory.

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Linux Basics
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Displaying the Contents of a File
cat password.txt
This command lists the contents of the passwords file.
Creating a Directory
mkdir directoryname
The process is the same as in Windows.
Changing the Directories
cd/pentest/enumeration
Changing the directories is very simple. It works as in Windows. However, we use / in Linux 
instead of \ for changing the directories.
Windows
C:/windows/settings
Linux
/pentest/web/scanners
Creating a Text File
touch hack.txt
This command creates a text file with the name hack.txt.
Copying a File
Cp source target
cp /var/www/filename /pentest/web/filename
This command will copy the file from the 
/var/www
directory to the 
/pentest/web/
directory.
Current Working Directory
pwd
This will return the current working directory.
Renaming a File
mv oldfile.txt newfile.txt

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Ethical Hacking and Penetration Testing Guide
There is no command specifically for renaming files inside Linux; however, you just need to issue 
the mv command to rename the file.
Moving a File
mv hack.txt/pentest/enumeration/
This command will move the file hack.txt to the /pentest/enumeration directory.
Removing a File
rm file name
This is very simple, and it works for directories in the same way.