– Do neatly logout of their web application, before switching machines. As they keep the records, which would not let you login using a different machine till a session timeout which ranges from 0.5 to 6 hours.

– Spoof Your MAC Address, if you are using multiple laptops/desktops

use ifconfig utility:

MAC address can be changed very easily using ifconfig. Run the following command as root user.

#ifconfig eth0 down hw ether address

eth0 is the name of the interface/NIC which address is to be changed.

down means the NIC is to be shutdown before changing address.

hw ether means hardware address class is ether(which indicates ethernet).

address is the address which will used as the new mac.

After the successful execution of the command. start the NIC again using the command:

# /sbin/ifconfig eth0 up

– Release your IP after successful log out

# dhclient -r -pf  < path to the current dhclient pid file >

The path of current dhclient pid file can be found using

# ps -eaf  | grep dhclient

Path is usually /var/run/dhclient-eth0.pid or /var/run/dhclient-wlan0.pid

How did we achieve it ?

- Login to a remote machine using ssh

- play a video using cvlc ( command line vlc )

- record the video using istanbul session recorder ( if u are in linux )

- convert it to mp4 format using ffmpeg

ffmpeg -i file.ogg -sameq  file.mp4

- Overlay the sound using ffmpeg and .mp3 of the same video. As in the sound would have played on remote machine and hence istanbul session recorder would not capture it.

ffmpeg -i file.mp4 -map 0.0 -i file.mp3 -map 1.0 -acodec copy -vcodec copy -ab 128k -ar 44100 file.mp4

- Crop the video, if you want to remove stuffs of your desktop before upload

ffmpeg -i output.mp4 -croptop 50 -cropbottom 50 output1.mp4

File fetchrequest.sh

#!/bin/bash
while [ 10 -eq 10 ]

#Runs in a infinite loop checking request file at server B every second
do
if [ `env | grep -c lastCounter` = 1 ];then
newCounter=`curl -s http://serverB/requestFile.txt | tail -1 | cut -d: -f1`

#Reading request file at server B
param=`curl -s serverB/requestFile.txt | tail -1 | cut -d: -f2` #Extracting the request parameters
echo newCounter : $newCounter lastCounter : $lastCounter

#If there is a new request, sending a response back to the server B
if [ "$newCounter" != "$lastCounter" ]; then
echo "Need to send a response"
echo "Response URL : http://serverA/something.pl?action=something&param1&param2"

#Trimming of the response that needs to be send to serverB and storing it in a variable
output=`curl -s "http://serverA/something.pl?action=something&param1&param2" | grep 'cap\\|img' |
sed \ 's/<src>.*<\/src>//g;s/<cap>/\:/g;s/<\/cap>//g;s/<img>/\:/g;s/<\/img>//g'`
echo "Response received : $output"

#writing the response to a flat file to be FTPed to server B
`echo $output>"rp_$newCounter.txt"`
`export filename==rp_$newCounter.txt`
`echo ls -l "rp_$newCounter.txt"`
typeset -i responseSize=`wc -c rp_$newCounter.txt | cut -d" " -f1`
echo "Response size $responseSize"

#If the process response is garbled, small or null, sending a dummy error in FTP file
if [ $responseSize = 1 ];then
`echo "We are working , try later" > "rp_$newCounter.txt"`
fi

#making an FTP connection to serverB and launching the response file
`curl -s -T "rp_$newCounter.txt" -u username:password"ftp://serverB/rp_$newCounter.txt"`
echo "Uploaded the FTP file for $newCounter request"
`rm -f rp_$newCounter.txt`
echo "Deleting rp_$newCounter.txt after upload"

#Updating the request environment variable
lastCounter=$newCounter
export lastCounter
fi
else
lastCounter=`curl -s http://serverB/mobRequests.txt | tail -1 | cut -d: -f1`
export lastCounter
fi
done

The whole system works very well, and the requests are processed and response send to user. There are however limitations to this model.

Download the new version’s (say FC 10)  iso(DVD) image and save it to a disk drive partition. I used a pen drive for the same. It works very well for filesystems viz. FAT32,ext2 and not NTFS. Copy the image file to any directory say for example /mnt/FedoraCoreDVD.iso( Assuming, that pen drive is mounted at /mnt) . Mount the iso image in a directory(any) to extract the isolinux folder.

#mount -o loop /mnt/FedoraCoreDVD.iso /home/user/Fedora/

Copy the isolinux folder and paste it inside the boot folder.

#cp -r /home/user/Fedora/isolinux /boot

Now we need to make an entry in the grub file to boot the copied isolinux folder’s install.img

# cat /etc/grub.conf

______________________________

title Fedora Upgrade
root (hd0,8) ———–> should be your  partition containing the current linux installation (0->First Hard Drive,8-> Partition number on this drive )
kernel /isolinux/vmlinuz
initrd /isolinux/initrd.img
______________________________

Copy the isolinux folder also to the pen drive(/dev/sdb, mounted at /mnt in this case) and reboot the system. Select the ” Fedora Upgrade” option in grub and the normal installation/upgrade demon anaconda will start. It will ask for the option of disk partition and folder containing the iso image and iso linux folder, which is /dev/sdb1 in this case. Select the same and the upgradation works like a charm.

- Make sure libvirtd demon is running
- Allocate the space as per your needs viz hard disk, RAM etc
- This one is the key step, do not forget to add a cdrom (/dev/hdc) pointning to iso image of Windows XP Disc, as after the first boot, XP installation searches for the Windows XP disk and it cannot read the host’s CDROM.

Everything goes on smooth with all these parameters.

import java.awt.image.*;
import javax.swing.*;
import javax.swing.JComponent.*;

public class circles extends JFrame {
public static void main(String args[]) {
double d=Double.parseDouble(args[0]);
int diameter= (int)d;
circles ca= new circles();
ca.drawCircle(diameter);
}
public void drawCircle(int diameter) {
int x=0,y=0,radius;
JFrame frame=new JFrame();
JLabel lab;
BufferedImage bi=new BufferedImage (diameter,diameter,BufferedImage.TYPE_BYTE_GRAY );
WritableRaster raster=bi.getRaster();
double [] iPix=new double [diameter*diameter];
if(diameter%2 == 1) {
diameter-=1;
}
radius=diameter/2;
for(int i=0;i(radius)){
y=y%(radius);
}
else
{
y-=radius;
y=-y;
}
if((x*x+y*y)<=((radius)*(radius))) { iPix[i]=255; } else { iPix[i]=0; } }
raster.setPixels(0,0,diameter,diameter,iPix); lab=new JLabel(new ImageIcon(bi)); frame.add(lab);
frame.setVisible(true); frame.setSize(600,600);
}
}

compile the program as javac circles.java

run as java circles diameter_value

e.g. java circles 500