Bit more feedback on using this.
I have an external IDE hard drive that I use as a backup bootable drive using SuperDuper. In the background, Drive Pulse is monitoring my various drives and it started throwing up some errors on this drive. After reading a little bit around the subject and getting some very helpful answers from the company that provide Scannerz, I opted to reformat this drive but zero'ing out. This takes longer as it forces the drive to write zero's to every single block. If the drive controller encounters an error due to a bad block then it will re-map the bad block to one of the spare blocks. So in theory at the end of this process I would have a 500Gb drive with all 'good' sectors.
However this is not the whole story because determining whether a sector is bad or not depends on several variables. If the sector is well and truly knackered then there is no debate..it will get mapped out by the controller. But if the sector is 'weak' ...ie it requires quite a few attempts at reading .. then that indicates that the drive is starting to fail..at least in the region of these weak sectors. Now whether or not the drive controller will actually deem these weak sectors to be bad or not will depend on the parameters set by the drive manufacturer and over which we have neither control nor knowledge.
That is where Scannerz comes into its own. Having zero-formatted this drive, I ran Scannerz and should expect to see zero bad sectors. And indeed this is what I did see. But I also saw a lot of what Scannerz describes as 'surface scan irregularities' or weak sectors. And I saw a lot. Near 4000 of them which definitely suggests that the drive is on the way out. Scannerz does identify these sectors for you and you can then run stress tests repeatedly on these sectors to see if the same results occur.....which they will if the drive is going dodgy.
But drives being relatively cheap, I bought a brand new 1TB firewire drive and out of curiosity ran Scannerz on it before doing any writing to it. The result? Zero bad sectors and zero weak sectors. So as Hugh Bonneville says 'All good then'.
