Linux training is one of the best gifts

Human beings are social. Most of us believe in giving to our loved ones. Our loved ones could be a friend, brother, sister, son, daughter, spouse, mother, father, cousin etc. Most of us gift our loved ones occasionally such as on graduation day, birth day, anniversary and during the festival season of Thanksgiving, Christmas, New Years and on other occasions according to culture. Materialistic gifts last for a certain period of time and give happiness for some duration to our loved ones. Education as a gift is a wonderful idea. Education helps person to make a difference in their life. John Dewey said "Education is not a preparation for life; education is life itself." So when you gift education you are providing an opportunity to life.

You might find it ashtonishing to know that Linux training for Linux system administration can be considered as a gift of education for a loved one who could be a high school student, college student, engineer, scientist, or accountant. You pick the profession and you will be able to find out how Linux training for Linux system administration can help to improve their professional activity. But you may have a question, what is Linux?

Let us explore, what is Linux? Linux is an open source operation system. The biggest benefit of Linux is, it's free to use. For windows operating system, we are all paying the license fee, for Linux operating system. Linux is also GUI (Graphical user interface) as windows. You can execute routine task such as create new folder, create new file, edit file etc. as well as system maintenance task such system monitoring for CPU usage, memory etc. using GUI.

There are a number of Linux flavors available in the market such as Ubuntu, Suse, Red hat Linux, Fedora etc. Now days Ubuntu is pretty popular in the market because of its user friendly features. You can build your desktop as well as server using Ubuntu. All Linux flavor has a common command, so if you know one type of Linux, you will be comfortable with all Linux types,including UNIX and AIX. There could be some differences in the commands for AIX and UNIX, but most of the Linux commands work for AIX and UNIX.

You might be wondering, how easy is it to get Linux training for Linux system administration at your own – time and pace? Only the knowledge of e-mail is required to start Linux training. IcanXplore – learn from any corner has made Linux training for Linux system administration available around the world at your own time,own pace, 24x7, and it's online. A person can learn from any corner of the world having a desktop or laptop connected with the internet. The typical Linux training duration is 1 to 2 weeks. IcanXplore allows 3 to 4 months for Linux training with all resources, and tools required.

So gift Linux training for Linux system administration education, and make a difference in your loved one's life. You might be thinking that they are educated and working so it might not be worth to gift Linux training as a gift. But think in different way for Linux training. If they are educated and working, Linux training for Linux system administration is also best because they could transform their knowledge and experience in to a product and they can change the world. That's why Linux training is one of the best gifts in education.

There is a creativity in everyone.The person needs a little support and he or she could innovate something that does not exist in the world OR make it better. So gift Linux training for Linux system administration and inspire others for education.

How to Hide Secret Data in image and audio files Ubuntu / Debian: Steghide

steganography is the technique used for hiding various data in different type of image and audio files with out changing the basic characteristics of file. Steghide is a utility for steganography. The color- respectivly sample-frequencies are not changed thus making the embedding resistant against first-order statistical tests.

Features include:
* Compression of embedded data
* Encryption of embedded data
* Embedding of a checksum to verify the integrity of the extraced data
* Support for JPEG, BMP, WAV and AU files

How to install steghide in Ubuntu / Debian
Open a terminal
$apt-get install steghide (or Use Synaptic Package Manager)

Basic Usage
$ steghide embed -cf picture.jpg -ef love.txt
  Enter passphrase:

  Re-Enter passphrase:

  embedding "love.txt" in "picture.jpg"... done

This command will embed the file love.txt in the cover file picture.jpg

After you have embedded your love letter love.txt data as shown above  and you can send the file picture.jpg to your lover.

Now How to extract file

$  steghide extract -sf picture.jpg
Enter passphrase:
the file "love.txt" does already exist. overwrite ? (y/n) y
wrote extracted data to "love.txt".

This will give file information

steghide info picture.jpg
"picture.jpg":
  format: jpeg
  capacity: 1.2 KB
Try to get information about embedded data ? (y/n) y
Enter passphrase:
  embedded file "love.txt":
    size: 34.0 Byte
    encrypted: rijndael-128, cbc
    compressed: yes

How to Synchronize a local directory with a remote directory using rsync in ubuntu

Most of the system administrators need to sync some of  their local folder to remote folder. You can do this with a simple command line utility rsync. This will synchronizes files and directories from one location to another , securely by using  delta encoding. It will synchronize files across the network by transferring only data that has changed.

Open a terminal

$sudo apt-get install rsync

$ rsync -r -a -v -e "ssh -l shibu" --delete 192.168.0.5:/var/www/ /home/shibu/public_hrml

$ rsync -r -a -v -e "ssh -l shibu" --delete ceattingal.ac.in:/webroot/ /local/webroot 

rsync command common options

• --delete : delete files that don't exist on sender
• -v : Verbose
• -z : compress file data
• -e "ssh options" : specify the ssh as remote shell
• -a : archive mode
• -r : recurse into directories

Script for Finding Size of All Folders in Linux

Some users will eat lot of space in the system by storing unwanted files. This bash script will help you find which folder using more space.

Open a terminal
Then cut & Paste the script

for f in * ; do if [ -d "$f" ]; then du -sh "$f" ; fi done | sort -n

How to Change Sudo Password Remembering Time in Ubuntu

When You use 'sudo' command it will ask for password in First time and will remember password for 15 minutes. It is a security hole for sensitive systems.
You can change sudo Password Remembering Time in Ubuntu .

Open a terminal and type
$ sudo visudo

In Ubuntu, visudo uses nano text editor, and what it does is edit the / etc / sudoers.tmp

Check for the line as shown below

Defaults        env_reset


Change it to

Defaults        env_reset , timestamp_timeout = X

Where X is the time that we remember the sudo password, if we put 0 (zero) that we always get the request.

Finally to save the changes, press Ctrl + X and said yes.

How to Recover Ubuntu after a Partial Upgrade

If your Ubuntu machine is nor working properly after a partial upgrade and have a have broken the system dependencies tree, You can recover it by using a  simple command that reinstalls all the installed packages and reconfigures them automatically.This will take a long time to complete.

$sudo dpkg-reconfigure -phigh -a

You can try the following command first

$ sudo apt-get install -f

How to setup Google Public DNS in Ubuntu 9.10 Karmic Koala

DNS (Domain Name Server) is basically a system to convert domain names into IP addresses. Domain names are easier to understand, memorize and write for humans while computers only use IP addresses to communicate.

In most of the  case, Internet Service Providers  providing the DNS servers to the customer. User can change it, the  reasons to switch to other DNS servers for performance, privacy and censorship. Most of the people using OpenDNS as the first alternative, But Now Google Public DNS is available and the performance is much better.

Now How to set up Google Public DNS in Ubuntu

Select System-->Preferences-->Network Connections

Select  the type of connection you have. For this example, we will use ‘Wired’.

Under ‘Wired’, highlight ‘Auto etho’ and click on ‘Edit’.

Now,  Inside 'Editing Auto etho' window, click on ‘IPv4 Settings’ tab. and select 'Automatic (DHCP) address only'

Put these nameserver addresses as your ‘DNS Servers’:8.8.8.8, 8.8.4.4

Click ‘OK’ and reboot your machine.

NOTE:

For avoiding  your settings get revoked after reboots, you may need to make the following changes via the command line:

$ sudo cp /etc/resolv.conf /etc/resolv.conf.auto
$ gksudo gedit /etc/dhcp3/dhclient.conf
# append the following line to the document
prepend domain-name-servers 8.8.8.8, 8.8.4.4;
# save and exit
$ sudo ifdown eth0 && sudo ifup eth0