Linux File System Corruption and Recovery

Although, Linux is a reliable and stable operating system, but sometimes it may crash unexpectedly. While booting a Linux system, you may get the below given error message:

“ext2fs partition type 0x83. ....ext3-fs: journal inode is deleted....

mount: error 22 mounting ext3 error 2 mounting name switch root: mountfailed:22 umount/initrd/dev failed:2

kernel panic - not syncing.”

After receiving this error message, Linux system could not be started.

Cause
Problems occurs when the system gets shutdown expectedly (possibly due to power outage, hardware failure or kernel bug) and file system does not get un-mounted.

Maximum file system issues are negligible ones, caused by the file buffers not being written to hard disk, like removed inodes are still in use. In maximum of the situations, file system check would be able to identify and repair these anomalies automatically.

If the file system problem is more severe (like the problems caused by faulty hardware like bad memory chip; you should keep in mind that file system corruption might happen frequently in such cases). The file system check might not be able to detect the problem automatically.

The grave situations usually, but not always, occur when your root Linux file system gets corrupted. In such situation, you will get the above mentioned error message and the OS will drop you in a shell, allowing you to perform manual file system repair and finally Linux recovery.

The Linux recovery shell un-mounts all the file systems and then mounts root file system in ‘read-only’ mode. It will give you to perform complete file system checks with the application of appropriate utility. Likely you can run fsck on the damaged file system, which might resolve the problem.

Though, the above mentioned method works in some conditions of minor problems with file system, but it can not fix the severely damaged file system. In such situations, you require to format the hard drive and reinstall the OS. But before this, you have to perform data recovery Linux to save your important data.

Converting Linux File System from Ext3 to Ext4

The (Fourth Extended File System) EXt4 is an latest and effective journaling file system that is originated as successor of Ext3 file system. It gives high performance and removes 64-bit storage limits of earlier file systems. The file system helps backward compatibility with the Ext3 and Ext2 file systems. Thus it is possible to mount Ext2 and Ext3 file system as Ext4. To get benefit of these advanced features, you require to change file system from Ext3 to Ext4. Before changing the file system, you should require to create full backup of your data as failure of this process may lead to data loss and require Linux recovery to be resolved out.

Changing a non-root file system

Changing Ext3 file system, which can be unmounted, this is simple process. Follow underwritten steps for conversion:

• Unmount the volume.

• Run file system check using fsck.ext3 command to make sure that it is in sane situation.

• Enable new features of Ext4 on file system using tune2fs command.

• Run fsck.ext4 command. It will find errors that are usual. Let the command fix them.

• Edit /etc/fstab file to make it “Ext4” in place of “Ext3” file system for /home.

• Mount your new file system.

Changing a root file system

Changing the root file system is quite tricky as you won't be able to unmount it since your computer is running on it. Go through the given below steps to convert your root file system:

• First thing is to change /etc/fstab file as “Ext4” in place of “Ext3” for root volume.

• Remount the root file system as read-only.

• Check your file system using fsck.ext3 command. It will then restart your system.

• Enable all Ext4 features on root file system.

• Check your root file system for errors using fsck.ext4 command.

Though, it is a good idea to convert your file system from Ext3 to Ext4, but in case if the process fails and you do not have complete backup of your precious data, you might encounter serious data loss and need to carry out data recovery Linux.

Recovery is best possible using third party Linux Recovery Software. The applications recovers your data in most of the data loss situations, without demanding sound and prior technical skills from you. With read-only and non-destructive conduct, Linux data recovery software are absolute safe to use.

Mistaken Formatting in a Dual Boot System and Linux Recovery

Dual boot or multi boot is a system in which two OS are installed on a single hard drive, letting you boot from either of the OS. The boot loader is a program which allows you to have dual booting.

General combination of OS exercised in dual booting includes Linux and Windows. The dual booting allows you to use features and functions of both of the OS on a single computer. Dual boot systems are mostly useful for programmers and testers.

Although, dual boot systems are useful but sometimes they can also cause many problems. A minor mistake made by the user while making a dual boot system can lead to the several catastrophic problems.

A common mistake made by the users, while making a dual boot system, is selecting “prepare hard drive” option. This option appears you when you install Windows operating system on a Linux system, in order to make it multi boot.

When you use this option, all of the hard drive partitions and stored data gets deleted. After that new partitions are created and the operating system is installed. When the installation will complete, you will have a blank hard drive without any operating system and data. Everything, which was previously stored on the hard drive, will be deleted.

Data loss and hard drive partition loss is the worst case scenario which a computer user, either general or professional, could face. It can cause several nightmares and can possibly put you out of the business.

In such circumstances, it becomes really important to recover your precious data from the formatted hard drive to save you and your business. The data recovery in these cases needs to be performed for the Linux data.

The data recovery Linux is possible through the use of Linux data recovery software. Linux recovery software is the applications, offered by the several data recovery companies, to handle all the data loss situations.

A powerful data recovery Linux software does a thorough scan of the hard drive and extracts data up to the maximum level of possibility. To ensure the absolute Linux data recovery , selecting powerful Linux recovery software of trusted brand is worth.

“No such file or directory” Error in Linux

Sometimes you try to install device drivers on your Linux system, you might fail to do it. It could be due to non compatibility of the OS Kernel with your device driver or device.

To resolve this issue, you require to install the latest version of Linux kernel. It may include ‘forcedeth’ patch, which is capable of resolving most of the non compatibility issues.

In some situations, after installing the latest version of Kernel, when you reboot the Linux system, you might face the following error message:

“fsck.ext2: No such file or directory while trying to open /dev/hda8. The super block could not be read or does not describe a correct ext2 file system. If the device is valid and it contains an ext2 file system (and not swap or ufs or something else) then the super block is corrupt, and you might try running e2fsck with an alternate super block: e2fsck -b 8193 fsck failed.”

After this error message, neither the system boots nor any file can be accessed.

Root Cause Problem

As stated in the error message, this problem generally occurs due to super block corruption or file system corruption.

è Super block and file system are two most important data structure of Linux system. Proper functioning of both these is necessary to ensure effective working of the system.

After corruption, the OS could not locate the file and thus can not retrieve it.

Resolution

To resolve this problem, you need to install a fresh copy of super block and file system. It is possible through formatting of the hard drive and reinstallation of OS.

Though, it will remove the errors but will also erase all the data stored on your hard drive. It is the worst scenario of data loss and needs Linux data recovery to get it fixed.

Linux data recovery is feasible with the application of third party Linux recovery software known as Linux data recovery. Linux recovery software is easy to use and thus allow you to have simple and fast data recovery Linux.

“Superblock Does Not Describe Correct”Linux Error

“Superblock does not describe correct file system”

The error also describes that system is unable to read the superblock. Also, if device contains the file system, then its superblock is corrupt and fsck is required with an alternate superblock.

By other superblock , it indicates to its duplicate copies on disk. Linux maintains duplicate copies of Superblock to avoid Linux Recovery requirements. These are located at different disk locations. The primary superblock lies at location 0 and group descriptors 1-6. However backup copies can be located using the following command:

# dumpe2fs /dev/sda2 | grep superblock

It will show the backup locations of superblock. Using these locations of superblock, file system can be attempted to mount. However if the process fails because of corrupt superblock backups, we require to refresh the file system by formatting the drive. It will create new copies of all file system structures. Lost data can be later restored using backup. However if no valid backup exists, Linux data recovery applications can help recovering.

Linux recovery software are the applications to recover lost data using specific scanning algorithms. These software can carry out recovery in all cases like superblock corruption, inode table damage, group descriptors faults and others. These software offer GUI and hence can be used easily. These products are safe for data as are designed as read-only. They offer quality features that assist users in recovery. But the software are not recommended to be installed on same drive to prevent overwriting.

´Currently has loop partition layout´ Linux Error and Recovery

Linux-based hard disk is divided into two major types of partitions: data partition and swap partition. Data partitions are the basic partitions that consist of system data, including that for starting and running the system in root partition. On the other hand, swap partition is responsible for holding hard disk extra memory and expanded system´s physical memory. In maximum of the Linux systems, fdisk is used to initially set the partition type. These partitions can be ext3 journaled, ext2, ext4 etc. But, sometimes you may observe certain issues with these partitions. Thus, Linux recovery experts suggest maintaining an updated backup of important data that is stored on hard disk.

Consider a situation, you try to mount a Linux partition to install a Linux distribution and encounter a similar error message:

"/dev/hdg currently has loop partition layout."

Where, name of partition, i.e. /dev/hdg, can vary. It can be /dev/had, /dev/sda tc.

Main reason of above error message are listed below:

If you are using a third-party boot loader on primary hard disk´s MBR, Disk Druid may fail to recognize your partitions.

Partition layout is damaged

Disk Druid is the tool to manage partitions and associate mount points. It is a graphical tool that displays existing disks and partitions in a defined format.

You can follow these steps to recover from the situation:

If boot loader has been the issue, uninstall the current boot loader and install GRUB on MBR of primary hard disk.

If partition table is damaged, backup all exiting and information files and folders and repartition the drive. Restore lost data using backup. If backup has not been taken, is damaged or incomplete, you can use commercial tools of Linux Recovery.

Linux data recovery software are advanced recovery applications that can scan drive affected from logical data loss. These applications use som algorithms that completely analyze existing disk structure. After locating missing files and folders, they compare their location information with that of existing ones. All the procedures are safe. Also, the interface provided is interactive and offer easy Linux recovery options.

'Grub loading stage 1.5..' Linux error and Recovery'

GRUB (GRand Unified Bootloader) is the standard boot loader used in Linux systems. When you turn on Linux based computer, the system uses MBR (Master Boot Record) to load initial bootstrap program. This MBR contains GRUB stage 1, which further loads GRUB stage 1.5 or stage 2 directly. GRUB stage 1.5 is located in 30 KB of hard disk after MBR. GRUB stage 1.5 loads stage 2, which presents a boot menu to select the required OS.

But sometimes, the system gets stuck at GRUB stage 1.5 and doesn’t boot anymore. In such critical conditions, you can’t access your stored data and need to use your recent data backup to restore lost information. But when data backup seems to be damaged, not updated, or is totally absent, you require using Linux data recovery applications that could restore the information intact.
Consider a live example, you try to boot your Linux-based system and boot process hangs, displaying the below error message on screen:
“grub loading stage1.5″
GRUB stage 2 doesn’t start and hence, you can’t select from the boot menu.


Possible causes of the above issue are:
Hard disk is not properly configured in BIOS
GRUB installation problems
File system and/or operating system issues.

Resolve the above situation, you should try these methods:
Make sure that your hard disk is set to autodetect in BIOS configuration
Try reinstalling GRUB. To do so, you need to boot the system using bootable diskette.
Run fsck to check and repair file system corruption. If problem continues, you need to reformat the hard disk and reinstall. To restore lost data, you should your recent data backup. But if backup is giving errors or is not complete to give required data, use Linux recovery applications.

Linux Data Recovery software are advanced tools that use powerful scanning algorithms to scan the affected media and restore lost information. Equipped with features like, automated recovery, read-only design, and complete documentation, these read-only tools serve as the most valid tools to recover lost data.

Red Hat 75% of the Paid Linux Market

A question put to company executives during Red Hat's (NYSE: RHT) Analyst day event webcast live from New York today.

The executives explained that open source leadership is key to Red Hat's success, but that the firm is also branching out into other areas so that its success won't hinge solely on technology.

Moving forward, Red Hat is planning to develop a combination of OEM and channel partner relationships.

Red Hat's Analyst Day event comes on the heels of another successful quater that saw the company grow both revenues and net income.

According to Red Hat Executive Vice President Paul Cormier, Red Hat now represents 75 percent of the paid Linux market, easily beating out other players in the sector such as Novell's SUSE Linux and Canonical's Ubuntu.

In the middleware market, Cormier said that Red Hat's JBoss division now commands one third of the market with its commercially supported JBoss server. According to Cormier, the other two thirds of the middleware market are made up of non-paying JBoss users and IBM WebSphere users.

Red Hat's leadership role also extends to its direct participation in the Linux kernel development process. A recent report from Linux foundation named Red Hat the leading corporate contributor to Linux, though overall contributions have come from more than 500 organizations.

In light of the high volume of contributions to the Linux kernel, Red Hat CTO Brian Stevens said it's important to view Red Hat's position as one of leadership, rather than power. In Stevens' view, the power is the larger Linux ecosystem with its hundreds of contributing corporations, which helps explain why Linux is an attractive technology for enterprises.

"It's not just about making a bet on Red Hat," Stevens said. "It's about making a bet on all of us."

Descriptor Table Corruption and LILO errors

LILO or LInux LOader is the standard boot loader used for Linux systems. Instead of the file system type, it can used in boot sector of partition or MBR. When you start the system and LILO loads, it performs a lot of steps and displays the word ‘LILO’. With each letter you see on the screen, it indicates that it has successfully completed a task. but if LILO fails at some stage, you find that the complete word ‘LILO’ is not displayed and hence you can’t boot Linux and access your data. To restore the lost data, you require to use a recent data backup. However, if data backup is not available, invalid or not up-to-date, Linux data recovery solutions can be used to extract the lost or inaccessible data. Consider a situation, you start the Linux system and the boot process halts with three letters ‘LIL’ on the screen. After the happening of this issue, you can’t boot the Linux system.

The above issue occurs if descriptor table is corrupted or damaged. The space on a Linux based hard disk is divided into blocks, which are further organized into block groups. Each of these block groups is described by a group block descriptor. Descriptor table is the index table of these group block descriptors.

To resolve this issue, you require to carry out these methods: You should first need to verify that disk parameters in BIOS (Basic Input Output System) are correct. Try reformatting the partition and reinstalling LILO. You need to restore the lost data using an updated backup. But if you face some issues with the backup, you can use Linux recovery applications. If the problem persists, you should run fsck to check and correct any corruption issues. Reformat the hard drive if fsck fails to fix file system problems and restore data from backup. Linux data recovery software are robust applications that recover and restore lost data safely. Such software use powerful scanning algorithms to locate missing information. In addition, they provide interactive interface, automated recovery procedures and to-the-point documentation .

Recover Linux data using Linux Data Recovery Software!

Recovery is a very important and commonly happens nowadays. Someone who suffer from a data loss and then realize and think that is there any services available which can recover data and save their important information. Problems can be resolved with the help of data recovery software companies. These software are made according to the platform. On windows platform there are different software and on the Linux platform, there are Linux Data Recovery Software. The Linux data recovery software provides you the software which you require when your files have been lost, corrupted or inaccessible. It can recover everything which has been lost from any data disaster or loss situations.

The most common reasons of having data lost are:
1. Virus Attacks
2. Disk Formatting
3. OS Corruption
4. Server Corruption
5. Unexpected System Shutdown
6. Human Errors
7. Hardware Failure

Linux Recovery is advance recovery software that recovers lost or deleted to formatted data. It can recover from a small laptop to a large enterprise server. It can recover all the items from lost/missing volume of Linux. The Linux Data Recovery Software supports recovery from the Ext2, Ext3 and Ext4 Volume of Linux OS. Recovery from lost, corrupted or missing partitions can also be done using Linux data recovery software.

Features:

1. EXT2, EXT3 Partition Support
2. Recover files from deleted, formatted, damaged or corrupted partition on Linux Platform
3. Recover & Restore lost data from lost files & folders
4. Recovers even if the super block or Inode List is damaged
5. File Recovery from IDE/EIDE/ATA & SCSI hard drives
6. File filtering feature that recover particular files with specific extensions
7. Load Log Feature, which resumes data recovery process later to save time
8. Find Features, which can search specified file from the list of recovered files

Linux data recovery software is a read only & non destructive utility that will help you in the worst conditions and recovers all the vital data. The two volumes Ext2 and Ext3 are new file system of Linux OS. Ext2 or second extended file system was the standard file system used on Linux OS for a number of years and still in use. It is quite fast and set a benchmark of standard. Its successor came with the name of Ext3, which is a journalled file system and is completely compatible with Ext2. The Linux data recovery software is totally compatible with the all these file systems and is very easy to use. So if you are facing any data loss or related problem with your Linux based computer then get the Linux data recovery software now.

Ext3 File System Corruption and Its Recovery

Ext3 file system is a journaled file system which is mostly used by the Linux kernel. It is the default file system for many Linux distributions. Important file system in ext3 file system is journal., hence called as journaled file system. Major drawback with ext3 file system is that it doesn’t support checksumming while writing to the journal and due to that the file system gets closer to corruption and need of Linux data recovery is felt. Checksumming is generally defined as an error detection technique if the file is corrupted. But the main cause is that the ext3 doesn’t support this feature, recovering from corrupt journal can damage all metadata information of file system.

System crash is recoverable if the file system in-use supports journaling. But in ext3, if the mounting options in /etc/fstab don’t include barrier=1 as enabled plus hard drive is performing out-of-order write caching and system gets crashed, ext3 catches risk of corruption.

This barrier feature is disabled by default in all of the Linux distributions, except in open SUSE, and so these systems can lose data there is a crash. Also, if user tries to use the mount option for ex3, a warning is issued about barriers is not supported. In such conditions also the system gets crashed.

In all the above situation the required blocks could be written, if user commits transaction and system crashes, it will reboot. During this, log replays and incomplete disk writing will be carried out with damaged journal information. This cause into overwriting of normal data with that of damaged and hence file system gets corrupted. Data under these situations can be recovered with the help of linux recovery application. One best thing is that the successor of ext3 i.e. ext4 supports journal checksumming.

There are so many applications in market, available as Linux recovery software which can recover lost data from Linux systems with corrupt file systems. These data recovery linux applications can be used easily without any prior sound technical knowledge. These software are safe for recovering data as they are of read-only design.