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

[Richard B. Gilbert]

On 7/11/2011 2:51 PM, 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?

For SLOWLY increasing error counts, I'd have a look at the error log to 
see what's going on.  If you are getting errors, your hardware is trying 
to tell you something.  Sometimes, it's telling you REPLACE ME ASAP!

You had better be paying attention!

If you can't interpret the errorlog, your Field Service Engineer can.
Yes, he, or she, costs money.  If your system is business critical, 
spend the money!

>
> Obviously, physically bad sections of a disk can cause errors, but what
> are other causes of error on physical disks and on shadow sets?

Users!  I recall a user many years ago who took a two week vacation and
left a program running the filled a disk directory with several 
thousands of small files!  All those files were cataloged in the SAME 
DIRECTORY.

Take my word for it, a directory with fifteen thousand files does NOT 
WORK QUICKLY or well!
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