To Solve Kernel Panic Error

• Go to the rescue mode and follow the instructions.
• now type this command
  

· e 2fsck -pvy /dev/hda1 ( or hdb whatever is urs, if its not happening then try with only y option)

sd It will fix the problem automatically

• Now remove the disc n restart the system
  

Hard Disk Cloning in Linux

dd command does not copy files only it copies blocks also.

To make a clone of a hard disk /dev/sda on an empty hard disk /dev/sdb type the following command

dd if=/dev/sda of=/dev/sdb

Note:-

• here if specifies input file and of specifies output file.
• Wait untill the command is finished.
• Finally you will have an exact copy of the hard disk.
  

command to replace a word from a file.

Command to replace a particular string (as many times in a file) from a particular file

ls /full/path/offile | xargs perl -pi -e 's/word to search/wordto replace with/g'