Monday, June 8, 2015

How to get Previous commands quickly in Ubuntu / Debian Linux

How to get Previous commands quickly in Ubuntu / Debian Linux


  1.   You can use the up arrow to view the previous command 
  2.   Type !! and press enter for the previous command
  3.   Type !-1 and press enter for the previous command    
  4.   Press Control+P will also display the previous command

Saturday, June 6, 2015

How to Disable Bash History Temporarily in Ubunu / Debian Linux


How to Disable Bash History Temporarily in Ubunu / Debian Linux


 Some times we want to use password as command line argument. Storing your password in .bash_history file  is not a good idea.

use the following command

$  unset HISTFILE


it is only for current session. 

Saturday, January 17, 2015

How to install Drupal 7 in Beaglebone Black

How to Install Drupal 7 in Beaglebone black






Drupal is an Open source Content Management Platform for powering your website. It is written in PHP. you need Apache2, PHP and mysql for Installing Drupal.  Now the POSTCARD sized Linux powered Beaglebone Black can use as your Drupal Webserver. See a tutorial here

Monday, January 12, 2015

How to Control Servo Motors from Beaglebone Black



Lot of DIY projects are using Servo Motors. Controlling of Servo Motors are very easy compared to other Motors. Here You can see How to control a Servo Motor using Beaglebone Black PWM pins. (Link)

Friday, July 4, 2014

How to Hide Userlist from Login Screen in Ubuntu/debian Linux

How to Hide Userlist from  Login Screen in Ubuntu/debian Linux


For Hiding User list you need to edit lightdm configuration file.

$   sudo vi  /etc/lightdm/lightdm.conf

Add the following line to the bottom of the file

    greeter-hide-users=true

 Save the file and reboot your system .

  Now the  user list will be hidden

Tuesday, April 29, 2014

How to Install Graphical (GUI ) Users & Groups Management Tool in Ubuntu 12.04

How to Install Graphical (GUI ) Users & Groups Management Tool in Ubuntu 12.04

The old Gnome User and Groups management tool is not available  in Ubuntu 12.04 LTS.


There is User Accounts available  under the System setting, but  you cannot administer groups.

You can solve this problem by installing the utility gnome-system-tools which is available in Ubuntu software repository.

How to install gnome-system-tools

Open a terminal and run the following command . or install it using synaptic Package manger.

$ sudo apt-get install gnome-system-tools
 
 
 

Tuesday, April 22, 2014

How to take system backup Using tar command in Ubuntu Linux




How to take system backup Using tar command in Ubuntu Linux


The following is an exemplary command of how to archive your system.
tar -cvpzf backup.tar.gz --exclude=/backup.tar.gz --one-file-system / 
To understand what is going on, we will dissect each part of the command.
  • tar - is the command that creates the archive. It is modified by each letter immediately following, each is explained bellow.
    • c - create a new backup archive.
    • v - verbose mode, tar will print what it's doing to the screen.
    • p - preserves the permissions of the files put in the archive for restoration later.
    • z - compress the backup file with 'gzip' to make it smaller.
    • f - specifies where to store the backup, backup.tar.gz is the filename used in this example. It will be stored in the current working directory, the one you set when you used the cd command.
  • --exclude=/example/path - The options following this model instruct tar what directories NOT to backup. We don't want to backup everything since some directories aren't very useful to include. The first exclusion rule directs tar not to back itself up, this is important to avoid errors during the operation.
  • --one-file-system - Do not include files on a different filesystem. If you want other filesystems, such as a /home partition, or external media mounted in /media backed up, you either need to back them up separately, or omit this flag. If you do omit this flag, you will need to add several more --exclude= arguments to avoid filesystems you do not want. These would be /proc, /sys, /mnt, /media, /run and /dev directories in root.


Tuesday, December 31, 2013

How to Install GRUB Customizer 4 in Ubuntu / Debian linux

GRUB Customizer is a graphical front end  for managing famous boot loader GRUB 2, 




Howto Install Grub Customizer


$ sudo add-apt-repository ppa:danielrichter2007/grub-customizer

$ sudo apt-get update

$ sudo apt-get install grub-customizer

Sunday, December 29, 2013

Shutdown your ubuntu / Debian system with a USB Pendrive

Shutdown your ubuntu / Debian system with a USB Pendrive

It is for fun !!! and a utility!!!

First  find out the vendorId and productId of your USB stick:
$ lsusb
 
my output
Bus 002 Device 002: ID 13fe:3600 Kingston Technology Company Inc.  
 
here
13fe - vendor Id
3600 - Product Id

Now create a file in: /etc/udev/rules.d/
 
I was created file :  100-usb-device-action.rules 
Then add the following line.
ACTION=="add", ATTRS{idVendor}=="13fe", ATTRS{idProduct}=="3600", RUN+="/sbin/shutdown -h now"
 
Substitute your vendorid and ProductID
After saving the file . Just plug your USB Pendrive in any USB Port . Your System will Shutdown!!!!

Thursday, October 31, 2013

Nikto : Open Source Web Server Scanner for Ubuntu / Debian Linux


Nikto is an Open Source (GPL) web server scanner which scans your webserver against more than 6500 potentially dangerous files/CGIs, checks for outdated versions of over 1250 servers, and version specific problems on over 270 servers. It has a very good plugin support

What Nikto can do.

    SSL Support (Unix with OpenSSL or maybe Windows with ActiveState's
    Perl/NetSSL)
    Full HTTP proxy support
    Checks for outdated server components
    Save reports in plain text, XML, HTML, NBE or CSV
    Template engine to easily customize reports
    Scan multiple ports on a server, or multiple servers via input file (including nmap output)
    LibWhisker's IDS encoding techniques
    Easily updated via command line
    Identifies installed software via headers, favicons and files
    Host authentication with Basic and NTLM
    Subdomain guessing
    Apache and cgiwrap username enumeration
    Mutation techniques to "fish" for content on web servers
    Scan tuning to include or exclude entire classes of vulnerability
    checks
    Guess credentials for authorization realms (including many default id/pw combos)
    Authorization guessing handles any directory, not just the root
    directory
    Enhanced false positive reduction via multiple methods: headers,
    page content, and content hashing
    Reports "unusual" headers seen
    Interactive status, pause and changes to verbosity settings
    Save full request/response for positive tests
    Replay saved positive requests
    Maximum execution time per target
    Auto-pause at a specified time
    Checks for common "parking" sites
    Logging to Metasploit
    Thorough documentation

Official site
To install in ubuntu / debian
$ sudo apt-get install nikto

Full installation of nikto will offer lot of options
$ nikto will give the list of options

For simple test

$ sudo nikto -h www.yoursite.com

output will we like this
abc@abc-desktop:~$ sudo nikto -h www.xxxx.com
- Nikto v2.1.4
---------------------------------------------------------------------------
+ Target IP:          202.18.233.233
+ Target Hostname:    www.abcx.com
+ Target Port:        80
+ Start Time:         2013-10-32 08:29:09
---------------------------------------------------------------------------
+ Server: Apache/2.2.22 (Debian)
+ Retrieved x-powered-by header: PHP/5.4.4-14+deb7u5

+ Server: Apache/2.2.9 (Debian) PHP/5.2.6-1+lenny3 with Suhosin-Patch mod_perl/2.0.4 Perl/v5.10.0
- Allowed HTTP Methods: GET, HEAD, POST, OPTIONS, TRACE
+ OSVDB-877: HTTP method ('Allow' Header): 'TRACE' is typically only used for debugging and should be disabled. This message does not mean it is vulnerable to XST.
+ OSVDB-0: ETag header found on server, inode: 3965147, size: 2857, mtime: 0x433a88acc26c0
+ PHP/5.2.6-1+lenny3 appears to be outdated (current is at least 5.2.6RC4)
+ mod_perl/2.0.4 appears to be outdated (current is at least 5.8)