Gave up waiting for root device. Common problems: - Boot args (cat /proc/cmdline) - Check rootdelay= (did the system wait long enough?) - Check root= (did the system wait for right device?) -Missing modules (cat /proc/modules; ls /dev) ALERT! /dev/disk/by-uuid/614036b0-1c9a-4311-b452-c5c0d3762690 does not exist. Dropping to shell! BusyBox ............. (initramfs)_
Then i was searching in google to find a better way to rescue my ubuntu.i got several useful links from http://ubuntuforums.org/showthread.php?p=6582510, but nothing seems to be fine.
In some links, they have mentioned to edit the grub menu and add all_generic_ide at the end of the kernel like this
/boot/vmlinuz-2.6.31-23-generic root=UUID=4614036b0-1c9a-4311-b452-c5c0d3762690 ro quiet splash all_generic_ide, but this trick also failed.
Later, i booted my pc with ubuntu 9.10 live cd and choose the option try ubuntu without install.Once i logged in, then searched for my root partition using Gparted(Gnome Partition Editor). Gparted will placed under System -> Administration.For me it is /dev/sda5.
Now, i restarted my pc and made the system to boot from hard disk.Then i enter into the grub menu.
1)Press 'e' on your keyboard to edit the boot config
2)Press the down arrow key to reach the 'kernel' boot parameter
(/boot/vmlinuz-2.6.31-23-generic root=UUID=4614036b0-1c9a-4311-b452-c5c0d3762690 ro quiet splash)
3)Instead of UUID=4614036b0-1c9a-4311-b452-c5c0d3762690 replace it with /dev/sda5
(/boot/vmlinuz-2.6.31-23-generic root=/dev/sda5 ro quiet splash)
4)Now press CTRL+X to boot the grub.
Finally my ubuntu was rescued, starts booted from the hard disk and doesn't find the boot error later on.