10 Apr
2007
10 Apr
'07
6:56 p.m.
I suppose in an ideal world I'd assume that
catastrophic failure of the media
could happen very quickly - so priority is to get a snapshot of the disk onto
modern storage before that happens.
The failure mode I've seen is oxide/binder coming off, clogging the head and
carving little concentric rings in the media :-(
Once the buildup starts, S/N ratio goes into the toilet, so the inner tracks
often have errors.
One of the techniques I've thought about to mitigate this is, as you say, just
snapshot all of the data without analysis, to avoid sitting on a track for a
minimal number of rotations, stagger-read tracks, or read them in inner to outer
track order.
There doesn't seem to be any obvious visual indication that the binder will strip
off a disc, oddly enough. You'd think there would be something like physical
discoloration when this was likely to happen.