Living with Bad Sectors on a Hard Drive
I have repaired computers for many years. Whenever I see SMART triggered (under normal operation) or a bad sector detected, I always replace the hdd. If you have ever dealt with bad sectors, then you know that they are like cockroaches; one bad sector means that more are likely to follow.
To fix things, one does not have to understand how things fundamentally work, which is nice for me!
I am curious about living with bad sectors -not recovering data from them. I guess my specific questions are as follows:
1. If an OS (Windows, *nix, or BSD) detects a bad sector during a disk checking operation, how exactly does it test the sector?
2. Once detected, what exactly does the OS do with the bad sector information? Will the info be stored physically on the drive or in the OS somewhere?
3. What exactly does a program like HDD Regenerator do with bad sectors (i.e. does it access some low-level disk firmware to tell the disk that it should not offer the bad sectors?)?
There are actually two types of problematic sectors: weak sectors (SMART: Current Pending Sector Count) and bad sectors (SMART: Reallocated Sectors Count). Programs like HDD Regenerator will try to repair the former. When a sector is confirmed to be bad (which usually happens automatically), its contents will be reallocated to the spare area. You can’t get rid of those, but as long as the number of weak/bad sectors doesn’t increase, you shouldn’t run into further problems.
I recommend using Hard Disk Sentinel which will report weak/bad sectors and also has a Surface Test including a repair mode similar to HDD Regenerator. You can download the latest version from the official website, and if you don’t want to pay for it, it’s easy to find a Hard Disk Sentinel 5.x activator online (confirmed working with 5.30 and probably also future versions).