[Discuss] unreadable sector

[blu at nedharvey.com (Edward Ned Harvey (blu))]

> From: discuss-bounces+blu=nedharvey.com at blu.org [mailto:discuss-
> bounces+blu=nedharvey.com at blu.org] On Behalf Of Jerry Feldman
> 
> I've brought this up before. One of the drives in my RAID reports an
> unreadable sector. I'm not worried about thisas this otherwise seems to
> be a serviceable driveand I take frequent backups.

Generally speaking, bad blocks on disk are like rust.  It's a chemical defect, and it spreads.  You should replace the drive in question.


> One question I might
> have is would I be better served by removing this from the RAID pair,
> and run a full destructive bad block scan 'badblocks -wsv /dev/sda | tee
> <some log file>'
> The bad blocks scan should (1) reallocate the bad blocks and also give
> me more detailed information on whether to replace the drive or not.

badblocks, by itself, only makes an attempt to identify bad blocks, and store them in a list usable by something else such as mkfs.  I don't know if you can *tune* with tune2fs, to incorporate a list of bad blocks.  You might have to recreate the filesystem in order for this to work.

I would bet more than the price of your disk, that if you monitor the bad blocks over time, you'll find they're spreading.


> Right now the information is only showing up in logwatch, and I occasionally
> get an email. A replacemnt costs right now about $75 for a 7200 RPM 1TB
> drive at MicroCenter.

Sure the old drive isn't covered by manufacturer warranty?