Why does GRBackPro doesn execute a real source file compare against the destination ones?
The function is named Verify because it doesn’t really compare files. Anyway, even if you do not zip GRBackPro will do a complete read back of the backed up files. This means that the file is verified as completely readable and consistent. This, of course, will not warrant you that a bit were changed since the write (due to a defective destination media) and in this optics you have less protection. You must know that when the media are broken, often (more than 90% of the times) they are no more able to read back the file and don’t simply change a bit. This is due to the hardware and firmware of the devices that for any disk sectors add some redundancy bits in order to correct the whole sector in case of 1-2 bit failures. The firmware also is aware of the problem and normally signals this to the system (for hard disk using S.M.A.R.T.) that some sectors are degrading. Optionally the hard disk is able to mark a whole zone as BAD and relocate it on some free tracks on the disk reserved for
