How to resolve "CG cg-number: BAD MAGIC NUMBER" in HP-UX

Cylinder Group in HP-Unix operating system is the primary component of file system that contains one or more consecutive disk cylinders. These cylinder groups are further divided into addressable blocks to organize the file structure within the cylinder group. The storage memory of these blocks is further classified into four main parts – boot block, Superblock, Inode, and data block. Corruption or damage in Cylinders groups occurs due to improper system shutdown, virus attack, and more. In most cases of corruption of these groups, you encounter an error message. A major hazard that you might encounter after the occurrence of the error message is inaccessibility of hard drive data. To overcome such situations, an ideal way is to restore the data from an updated backup. However, if no backup is available or backup fails to restore the required information, then you will need to use advanced HP-UX Recovery software that can comprehensively recover your inaccessible data.

Below is the error message tha ou receive when the cylinder group gets corrupted or damaged:

"CG cg-number: BAD MAGIC NUMBER"

Your hard drive data becomes inaccessible after the above error message appears.

Cause:

The root cause for the occurrence of the above error message is the corruption of cylinder group cg-number due to wrong magic number. The corrupted cylinder group is marked as needing reconstruction.

Resolution:

To resolve the above error message, you will need to reinstall HP-UX operating system. A clean reinstall of HP-UX operating system erases all the data from the hard drive. In such situations, the best possible way to recover the data from HP-UX based formatted hard drive partition is by using advanced HP Unix Data Recovery  application. Such HP-UX Data Recovery tools perform an orderly scan of the formatted hard drive by using high-end scanning algorithms. These recovery tools recover lost data post serious corruption scenarios including superblock or inode structure damage, LVM corruption, Cylinder Groups damage, and OLT corruption. With highly graphical user interface and advanced features, these tools are easy to understand without any prior technical understanding.

Stellar Phoenix HP UNIX - Data Recovery is a powerful and trust worthy HP-UX Recovery application. This non destructive utility is compatible supports HP-UX fe versions like HP-UX 10.x, 11 and 11i. It gets installed on Windows (2003, XP, 2000, NT3.51 and above, ME, 9x) and the affected HP-UX hard drive should be connected as slave.