If you are a Linux user, then you must have used a utility, known as Boot Loader. It provides different levers of functionality and support, through its different variations. Along with the boot operations, Linux boot loader also handles errors and helps you keep your system functional. Boot loader generally handles boot and memory errors at start up. However, in some cases, the boot loader can not fix the errors, which makes your system unbootable and unusable. In such circumstances, you can not access the data stored on your Linux hard drive and eventually face data loss. In order to extract lost data from the Linux hard drive in such situations, you need to opt for linux data recovery solutions.

Two most popular boot loaders of Linux operating system are:

LILO (Linux Loader)- It comes as default boot loader of all Linux distributions. As one among the oldest boot loaders, its strong Linux community accompaniment has enabled LILO to develop over time and remain useful as an operational modern boot loader. Some novel functionalities, such as exploitation of newer BIOS (Basic Input/Output System) functions and improved user interface, make this boot loader more stable and reliable.

GNU GRUB (Grand Unified Boot Loader)- It is considered as a replacement of LILO. It is based on original GRUB program and developed by Free Software Foundation. GRUB is reference implementation of Multi boot Specification that enables you to have various operating systems on same computer and select which one to use for booting.

Both these boot loaders allow Error Handling for proper functioning of your Linux computer.

Error Handling:

It denotes anticipation, detection, and finally, resolution of the operating system or application errors. The Linux boot loaders forestall most of such errors, recover your system from them when the errors occur, without affecting the system operations.

Although, boot loader error handling is a useful process, but if the critical errors can not be handled by Linux boot loaders, your system may become unstable. Such situations may cause data loss and require data recovery linux to be fixed.

Linux Data Recovery is possible using powerful and advanced linux recovery software. They are particularly designed to thoroughly scan whole Linux hard drive and extract all lost, missing, and inaccessible data. The applications are capable of handling virtually every type of logical data loss situations and enabling safe and easy recovery.

Stellar Phoenix Linux Data Recovery software recovers lost, missing, and inaccessible data quickly and successfully. It supports all major distributions of Linux operating system, such as Red Hat, SUSE, Ubuntu, Fedora, Mandriva, and Debian. The software recovers lost Linux data from Ext4, Ext3, Ext2, FAT32, FAT16, and FAT12 file system volumes.

The hard drives can be divided in one or more parts, known as partitions. The division of hard drive is described in partition table, stored in sector 0 of hard drive. Linux operating system requires at least one hard drive partition, namely for the root file system. It may use the swap files and swap partitions, however the latter are quite efficient. Thus, generally you may want second Linux hard drive partition devoted as the swap partitions. In some cases, improper use of hard drive management tools can cause data loss and need Linux Data Recovery to be sorted out.

On the Intel hardware, the BIOS (Basic Input/Output System) that boots up your system and can generally only access first 1024 cylinders of hard drive. Due to the same, you may need to create third hard drive partitions if your hard drive is large in size. This partitions is generally mounted on the /boot , for storing kernel image and some auxiliary files required at boot time, so that BIOS can access them.

You can create the manipulate the partition table in Linux using a menu drive program, known as fdisk. However, this tool can not understand the GPT (GUID Partition Table) and is not work with large partitions. Fdisk understands DOS partition table and BSD/SUN disklabels.

The Fdisk automatically obtains the hard drive geometry, if possible. It is not inevitably physical disk geometry (as modern hard drive don’t actually have physical geometry), but is disk geometry that is used for DOS type partition tables.

Generally everything works fine if only the Linux operating system is installed on your drive. But, in dual-boot configuration, you should let the Fdisk from other operating system create at least one partitions. While booting the Linux operating system, it considers partition table and attempts to derive what geometry is needed for effective cooperation with another operating system.

Before you proceed for any operation on your hard drive, it is recommended to create complete backup of your significant data. When you backup data using dd command, you need to be careful. A minor mistake may cause severe data loss and need Data Recovery Linux to be handled.

Linux Data Recovery is possible with the help of powerful third-party tools, known as Linux Recovery Software. The applications are particularly designed to carry out thorough scan of the drive and extract lost, missing, and inaccessible data from it.

Stellar Phoenix Linux Data Recovery is the most advanced tool for absolute recovery. The software recovers data from Ext4, Ext3, Ext2, FAT32, FAT16, and FAT12 file system volumes. It is compatible with all major distributions of Linux operating system including Red Hat, Debian, SUSE, and Fedora.

For example, you upgrade from Ubuntu 9.04 to Ubuntu 9.10. However, when the upgradation process gets finished and you attempt to boot your system, you receive the below error message:

“error: no such device : ba123456-7890-abcd-efghijklmnop

Failed to boot default entries
Press any key to continue”

Once the above error message appears, your system becomes unbootable resulting into inaccessibility of the hard drive data. In addition, the error message pops up every time you press any key.

Cause:

The cause for the error message is improper upgradation of Ubuntu.

Resolution:

Follow the below steps to resolve the above error message:

1.Boot your computer using Ubuntu 9.10 CD.

2.Start terminal and then log on as a manager in nautilus file manager.

3.Next, go to “/boot/grub/grub.cfg” and right-click grub.cfg.

4.Select Properties and select tab permissions. Modify the permissions of “owner:root” to “read and write”
5.Right-click grub.cfg and find the below entry:

### BEGIN /etc/grub.d/10_linux ###
menuentry “Ubuntu, Linux 2.6.31-14-generic” {
recordfail=1
if [ -n ${have_grubenv} ]; then save_env recordfail; fi

et quiet=1
insmod ext2
set root=(hd0,1)
search –no-floppy –fs-uuid –set ba123456-7890-abcd-efghijklmnop
linux /boot/vmlinuz-2.6.31-14-generic root=UUID=ba123456-7890-abcd-efghijklmnop ro quiet splash
initrd /boot/initrd.img-2.6.31-14-generic

6.Change the above entry to relatively simpler one, as done below:

### BEGIN /etc/grub.d/10_linux ###
menuentry “Ubuntu, Linux 2.6.31-15-generic” {
set root=(hd0,1)
linux /boot/vmlinuz-2.6.31-15-generic root=UUID=ba123456-7890-abcd-efghijklmnop ro quiet splash
initrd /boot/initrd.img-2.6.31-15-generic
}

7.Modify the permissions of “owner:root” to “read-only” and restart your system.

If you receive the error message even after following the above steps and your data remains inaccessible, then you will need to use Linux Data Recovery software to recover your data. Such Data Recovery Linux tools perform recovery in almost all data loss cases.

Stellar Phoenix Linux Data Recovery is an effective Data Recovery Linux application that supports recovery from all Linux distributions, including Caldera, Red Hat, SUSE, Sorcerer, Debian, Mandrake, etc. It is compatible with Ext2, Ext3, Ext4, and FAT file systems.