Technology And Computer|

Are you facing file system structure inconsistency errors? Are you unable to boot your Linux computer? This is due to problems with Linux file system. In such cases, operating system can not get required information to boot and thus you face odd behavior. This behavior renders your entire system inaccessible and unusable. In such circumstances, you may experience horrifying situations of data loss. Data loss is a very critical situation that creates need of Data Recovery Linux.

When you try to start your Linux computer, you may come across any of the below symptoms:

•    You encounter “Error 16: Inconsistent filesystem structure” error message while booting your computer. The system loops round and attempts to boot the system again, with the same error message.

•    When you select previous version of kernel at boot menu, the system starts booting, but runs “Checking filesystems” and does not give any error. However, when it goes to /boot directory, you get “Error reading block 49404 (Attempt to read block from filesystem resulted in short read) while doing inode scan.” error message.

•    You can get into the recovery mode, but can not run system maintenance tool.

•    When you run fsck utility from maintenance prompt, you encounter “short read” error.

If any of the above behaviors occur, you can not boot your system and it becomes inaccessible. In order to get your precious data recovered, Linux Recovery is required.

Cause

The above problem is caused by the Linux file system code for denoting internal error, which is returned by sanity checks of file system structure on hard drive not coping up with what is anticipates. It is generally resulted by a damaged file system or due to bugs in code handling in GRUB boot loader.

Resolution

File system corruption and boot errors call for hard drive formatting and operating system reinstallation. This replaces all the damaged system files and file system. However, it also removes all the data from hard drive and causes severe data loss.

In such events, Linux Data Recovery software come to your rescue. The applications are specifically designed to extensively scan the affected Linux hard drive and retrieve lost data. You need not have sound technical knowledge to perform Linux Recovery using these tools as they have interactive user interface.

Stellar Phoenix Linux Data Recovery software successfully recover lost, deleted, or inaccessible data from Linux hard drive. It supports recovery from Ext4, Ext3, Ext2, FAT12, FAT16, and FAT32 file system volumes. The software works well with all major versions of Linux operating system, such as Ubuntu, Fedora, SUSE, Debian, and Mandriva.

All the data files that are accessible in Linux based computers are placed in a big tree, called root directory and denoted as ‘/’, in an organized form. These data files might be spread out over various devices. The mount command in Linux operating system allows you to attach a file system on a data storage media to the root directory. However, if the file system is faulty and you run fsck utility to fix the problem after mounting the disk using this command, severe file system corruption occurs. It causes critical data loss situations and calls for Linux data recovery.

The mount command tells the Linux kernel to attach the file system found on your hard drive volume in the /dir directory. The previous owner, mode, and contents of the directory become invisible after mounting, and as long as the file system stays mounted, the /dir pathname refers to the root of file system on Linux hard drive volume.

The following three types of invocations of mount command don’t actually mount the volume:

·     mount -h- It prints the help message on screen.

·     mount -V- This invocation prints the version string.

·     Mount [-l] [-t type]- The option lists all the mounted file systems that are of type “type” on your Linux hard drive. The -l option adds labels (like ext2, ext3) in the listing.

In current versions of Linux operating system, it is possible to mark the mount and submounts as private, shared, unbindable, or slave. The shared mount gives you an option to create mirrors of the mount.

Mount is an essential process for accessing data from any Linux hard drive volume. If the drive is not mountable, it cannot be accessed. Sometimes, when you try to mount a Linux volume, you come across the following error message that puts you in need of data recovery Linux:

“Wrong fs type, bad option, bad superblock on /dev/hda8, missing codepage or helper program, or other error. In some cases useful info is found in syslog – try dmesg | tail or so”

This problem is caused by dirty or corrupt file system. In such cases, you need to use Linux recovery software to get your mission-critical data back. The Linux data recovery applications enable you to thoroughly scan the affected Linux hard drive using advanced scanning algorithms.

Stellar Phoenix Linux Data Recovery is the best solution to ensure absolute recovery in all Linux data loss situations. The software recovers lost Linux data from Ext4, Ext3, Ext2, FAT32, FAT16, and FAT12 file system volumes. It works well with all major distributions of Linux operating system, including SUSE, Mandriva, Red Hat, Debian, and Ubuntu.

Like other computer operating systems, Linux also comprise of various components, which include Superblock. Superblock is a significant metadata of the Linux operating system, which describes file systems on the Linux hard drive. The system components have interdependency and work together to keep your system functional. However, if any of these system components or data structures gets damaged, the system may not work properly and you can not access stored data from the hard drive. This behavior leads to critical data loss situations and require Linux Data Recovery to be fixed.

Under some situations, you can not mount your Linux file system and the data stored on the Linux hard drive volumes can not be accessed. Most of the problem occurs in a dual-boot system. When you try repairing your Linux file system on the root partition, process could not complete successfully. It renders your entire system inaccessible.

When you run fsck utility on the affected Linux hard drive, without ‘L’ option, you may come across the below error message:

“Leonzwei root # xfs_repair -nLv /dev/hdc3
Phase 1 – find and verify super block…
Bad primary super block – bad magic number!!!
Attempting to find secondary super block…
Found candidate secondary super block…
error reading super block 54 – seek to offset 57982058496 failed
unable to verify super block, continuing”

The repair process is interrupted after the above error message. In such cases, you need to identify the cause of this behavior and then perform Data Recovery Linux by resolving it.

Grounds of the problem

This behavior takes place because of corruption to the Linux Superblock. File system can not mount after Superblock corruption and thus your system can not boot up. Corruption may occur due to numerous reasons, such as virus infection, improper system shutdown, user errors, and more.

Solution

You can sort out this problem by replacing the damaged Superblock with its identical copy, which is maintained by Linux operating system to prevent such problems. However, if it is not possible, hard drive formatting is the only way to go. It actually removes all the data from hard drive and causes severe data loss. At this point, you need to use Linux Recovery applications to get your mission critical data back. The applications are particularly designed to methodically scan entire hard drive and extract all lost data from it, ensure absolute Linux Data Recovery.

Stellar Phoenix Linux Data Recovery is the most advanced and effective utility to ensure perfect recovery in all data loss situations. The software works well with all major distributions of Linux operating system, including Red Hat, SUSE, Fedora, and Debian. It Recover Linux from Ext4, Ext3, Ext2, FAT32, FAT16, and FAT12 file system volumes.

Are you unable to change the ownership of your mountable Linux hard drive volumes to make them accessible on LAN? Does the process fail with both root user account and local account? Actually, this behavior occurs if you do not have appropriate permissions to change the ownership of the disk or some significant system files are damaged. Since the system files are damaged, they can not even be accessed by the regular users. This causes grave data loss situation and calls for Linux recovery, if the backup is not updated.

As a practical example of this problem, you may encounter the below error message every time you try to change the ownership of mounted hard drive on Debian Linux operating system based computer:

“debian:/# chown -v ryan:ryan /mnt/hdc1
failed to change ownership of `/mnt/hdc1′ to ryan:ryan
chown: changing ownership of `/mnt/hdc1′: Operation not permitted
debian:/# chmod -v 777 /mnt/hdc1
mode of `/mnt/hdc1′ changed to 0777 (rwxrwxrwx)
debian:/# ls -l /mnt/
total 16
drwxr-xr-x 4 root root 16384 1969-12-31 17:00 hdc1
debian:/#”

The “Operation not permitted” error may also occur if you try to mount a Linux hard drive volume, access data from a volume, move data from a location to another, or change the active partition.

Root of the problem:

This behavior may occur due to any of the below reasons and put you in need of Linux hard drive recovery alternatives:

One or more attribute bits of the directory or file are set incorrectly. It prevents you from changing disk permissions using the chmod command.

The root directory, which is repository of all sub-directories and stored data, is damaged. Thus operating system is unable to read structure of the disk.

System data structures, like file system, superblock, and iNode are either missing or corrupt. These reasons are responsible for making your Linux hard drive unusable.

Resolution:

To fix this problem, you need to repair or replace the corrupted data structures with new ones. It is possible by formatting the hard drive and reinstalling the operating system. But, this process eventually removes all your data from hard drive and causes further data loss.

In such cases, Linux hard drive recovery software come to your rescue. They are advanced commercial utilities, which thoroughly scan your hard drive using high-end scanning methods and retrieve all lost data. The Linux recovery tools are easy and safe to use.

Stellar Phoenix Linux Data Recovery software successfully recovers lost, missing, inaccessible, and deleted data from Linux hard drive. The software salvages data from Ext4, Ext3, Ext2, FAT32, FAT16, and FAT12 file system volumes of all major Linux distributions like SUSE, Debian, Red Hat, and Mandriva.

The Linux operating system is supposed to be the most regularly updated operating system among its counterparts. Apart from this fact, for its advanced technology and features, a large number of users prefer Linux. But, in Linux, the user can not get everything preloaded just like Windows. There is an unique command for each operation in Linux and from the long list of regularly used commands, the ‘mount’ command lets the operating system to learn about the file system and lists in the file system hierarchy of the computer, which lets us access the the particular drives. However, sometimes, the ‘mount’ command fails to work and the OS can not be able to learn the drives resulting in the inaccessibility of them. In such situations of data loss or inaccessibility, Linux data recovery can help you recover your valuable data back.

There can be a possible file system corruption, which has led this abrupt behavior of the Linux system following the failure of the ‘mount’ command. The ‘fsck’ is a built-in command-line utility in Linux operating system, which checks the consistency of the file system and repairs the same, if finds any error. After encountering the above situation, if you try to mount the drives using the ‘fsck’ command, you may encounter some more error messages. The error messages may be read as below:

“[/dev/mapper]fsck -a /dev/mapper/mpath0p1
fsck 1.35 (28-Feb-2004)
ext2fs_check_if_mount: Input/output error while determining whether /dev/mapper/mpath0p1 is mounted.”

OR

“fsck.ext2: Bad magic number in super-block while trying to open /dev/mapper/mpath0p1
/dev/mapper/mpath0p1:
The superblock could not be read or does not describe a correct ext2
file system. If the device is valid and it really contains an ext2
file system (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 8193 <device>”

The above error messages clearly state that the file system has been corrupted. In order to resolve the issue, you need to boot the Linux system from the safe mode and run the ‘fsck’ command to repair the corruption. However, if the file system has been severely corrupted, ‘fsck’ simply exits without doing anything. In such a case, if you are an expert user, you can input the next super-block address or the size of the same to the ‘fsck’ command, which can help the utility to gather the information from the next super-block and do the job.

However, failing to the above resolution method, you need to opt for any Linux drive recovery software to bring back your precious data.

Stellar Phoenix Linux Data Recovery is an efficient as well as 100% risk-free Linux recovery utility of the current time. The utility has been trusted by a number of users for its power-packed scanning algorithms and ability to recover lost, deleted, formatted or inaccessible data from any troubled Linux drive irrespective of the complexity of the data loss situations.

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In Linux operating system, fsck is a useful utility that helps you to check file system integrity and fix the errors. It is helpful particularly in case of file system corruption, dirty system shutdown and operating system related issues. When improper system shutdown happens, fsck runs when you reboot the system and check file system integrity. But if fsck process gets terminated due to improper system shutdown or power failure, you might come across serious data loss issues. In such circumstances, you are required to opt for effective and powerful Linux Data Recovery solutions.

In a practical scenario where fsck process gets interrupted due to power outage, when you restart the system, all of your hard drive volumes are found to be inaccessible. It cause critical data loss situations. When you try to sort out the problem by using fdisk command on Linux hard drive, you see following message: “Warning: invalid flag 0×0000 of partition table 4 will be corrected by w(rite) Command (m for help): p Disk /dev/hdb: 203.9 GB, 203928109056 bytes 255 heads, 63 sectors/track, 24792 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System Command (m for help):”

Cause

As stated in the above error message, the problem is caused by corruption to partition table. It is an important data structure of Linux operating system that stores important information about hard drive partitions/volumes. It is a 64-byte table, which store four partition entries, 16 byte for each. Damage to the partition table means your operating system could not locate partitions on hard drive and thus can not access them. In other means, you need to carry out Data Recovery Linux for fixing this issue.

Resolution

In order to work around this issue, you need to format the hard drive and reinstall Linux operating system. It will replace the damaged partition table with new one, after that system will work perfectly. But formatting the drive would remove all the data from it and you face serious data loss situations. Linux Recovery in such situations is possible using commercial Linux Data Recovery software. The applications are completely safe and easy to use and perform absolute recovery in most of the data loss situations. Stellar Phoenix Linux Data Recovery is the most comprehensive solution for all types of data loss situations. It recovers lost data from Ext4, Ext3, Ext2 and ReiserFS file system volumes. The application is usable with all major distributions of Linux operating system.

In Linux operating system, you can re-size the hard drive volumes with preservation of your critical data stored on the volume, using Gparted utility. It can also be used for creating, moving and removing hard drive volumes. In some situations, resizing the hard drive volume might cause serious problems of data loss. Unsuccessful operation of disk resizing might render the disk volumes and stored data inaccessible. In these cases, you are required to opt for effective and powerful Linux Data Recovery software to get all of the missing, lost and inaccessible data. In a practical scenario, when you resize the hard drive volumes using Gparted utility in Linux, read/write operation may halt it and the hard drive might not mount.

When you try to access data from the affected hard drive, you come across a number of error messages. In such situations, if you run fsck command to detect and repair errors, it does not detect any problem and you encounter further error messages. The error message can be similar to the following one: At this point, your Linux system does not boot up and thus you can not access the stored data form hard drive. In these circumstances, you need to find out the cause of this issue and go for Data Recovery Linux to retrieve lost data.

Cause of this problem

This issue generally occurs due to corruption to the Superblock. It is one of the most critical database of your Linux operating system. The above error message indicates that your file system is severely damaged and thus the system can not work.

Resolution

The Linux operating system keeps redundant copies of superblock. You can use any of them to sort out the problem. You can search alternative superblock using ‘mkfs -n’ command. If you are unable to replace damaged superblock or the problem is with file system, you can go for hard drive formatting and operating system reinstallation. The process will replace all the damaged system resources and install a clean file system. Though above process can resolve the current problem, but it also has a drawback. Formatting the hard drive removes all of the data from it and cause critical data loss situations.

In these cases, you require Linux Data Recovery to handle the situation. Recovery is best possible using third part Linux Recovery software. The applications use high-end scanning techniques to thoroughly scan the affected drive and retrieve all of the lost, missing and inaccessible data. They are quite easy and safe to use. Stellar Phoenix Linux Data Recovery is the most excellent solution for all your Linux data loss problems. It supports recovery from Ext4, Ext3, Ext2 and ReiserFS file system volumes. The software is compatible with all major Linux distributions including RedHat, Fedora, Debian and Ubuntu.