[plug] re: RAID5 & Hot Spares

[Craig Ringer]

  > 400 + bad sectors, and almost totally unuseable. When I ran a disk 
test,
> it started with 400-ish bad sectors and finished with 440 (according to 
> SMART). Clearly, the SMART monitoring and drive testing doesn't work as 
> well as it should - but there's no user monitoring facility. In 
> retrospect, I think I would've gone for software RAID and saved $1200.
> 
> Implying that software RAID has advantages?

Well... only that software RAID is better than hardware RAID where the 
RAID hardware is not working properly and is eating your data. Oh, and 
if the RAID card dies you can be in for some interesting times with 
hardware RAID, but with software RAID ... what hardware? It doesn't care 
what chipset it's on, etc.

Good hardware RAID is basically impossible to beat. I just ended up with 
bad hardware RAID - or at least a dud example of it.

> I hope so because that is 
> what I need to use (for cost reasons) at the moment.   I'll hunt around 
> for a SMART daemon - would be nice if warnings of bad sectors could be 
> automatically e-mailed to the admin!

apt-get install ide-smart

unfortunately, the smartd isn't so great. I just run smartctl 
periodically and look at the output, since I no longer trust automatic 
monitoring to know what to look for as a failure indicator.