In your computer hard drive, file system has a really important role to play. they are responsible for systematic storage and access of data from the drive or volumes. be it ext2, ext3 or ext4, if it goes bad, all the data in your LINUX system becomes completely inaccessible. Sometimes, due to unexpected system shut down, virus infection or operating system malfunction, the file system of your LINUX computer gets corrupt. As the files system provide information about data areas in the system, the operating system fails to fetch any information from the damaged one and the data becomes inaccessible. However, with the help of any LINUX recovery software, all your lost or inaccessible data can be recovered.
In case of a corrupt files system, LINUX flashes various error messages on the screen. one of those error messages can be read as below:
Activating swap partitions: dup2:Bad file descriptor [FAILED]
Setting hostname Leshkow2: dup2Bad file descriptor [FAILED]
Grep: /proc/mounts: No such file or directory
Checking root file system
dup2: Bad file descriptor [FAILED]
After encountering such an error message, the entire hard drive or the corresponding LINUX volume becomes completely inaccessible. Here, the cause behind the above error message is the corruption of the ‘/dev/null’ entry inside the device inode permission. This means, file descriptor has been corrupted or missing and thus the OS has failed to locate the file, needed to mount the volume.
Following methods may help you resolve the above problem -
run the FSCK utility to repair the corrupt file system.
If FSCK fails, try the below steps:
Mount the root file system by running the command -
‘mount -n -o remount,rw /dev/hd0′
Note: Here, hdo is the root partition of your LINUX hard drive.
Run the command – ‘rm -rf /dev/null’ and remove the entry from ‘/dev/null’.
Run the command – ‘mknod -m 666 /dev/null c 1 2′. This will create a new writable entry.
Restart the system with the command ‘shutdown -r’ or ‘shutdown -h’. This makes the changes to take effect.
If you still getting the same problem and the LINUX volumes are inaccessible, for the volumes and restore data from backup. in case, if you do not have any valid backup, run any LINUX data recovery utility.
These data recovery utilities are designed to retrieve any deleted, formatted or inaccessible data back from the LINUX hard drive. With highly interactive user interfaces and clear instructions for each step, even a normal non-technical user can use these software, without any problem.