[Info-vax] rule of thumb for replacing bad disks based on error count

[BRAD at RABBIT.HSD1.MA.COMCAST.NET]

In article <ivfgof$vp9$1 at online.de>, Phillip Helbig---undress to reply wrote:
>Obviously, if I see the error count increasing quickly on a physical 
>disk, I will replace it.  My hope is that until I do so, HBVS will keep 
>my data safe.  (For really important shadow sets, I have 3 members; for 
>others, 2.)  But what about for SLOWLY increasing error counts?  And 
>what about errors on the shadow set itself, rather than on the members?
>

Speaking as a hobbyist - 

I have (at least) one spare disk drive available at all times.  Since I have no
FS to rely upon, it won't take much to convince me that I should swap in a new
disk for one that is gathering errors, even "slowly".

Once I swap in the new drive, I hunt the internet to find a good deal for my
"next" spare drive.

For my purposes, this general action plan is the most cost-effective (my time
and my money) solution.  YMMV.
[...]