> David's procedure should work, but I think he left
> out one step.  When creating a copy of the bad tape, you should
> "pad" the copy
> with "blank" tape blocks.  If you just copy the good data from the original
> tape starting just past the VOL1/HDR1/HDR2/TM on the copy, all the data will
> be in a different place (relative to the beginning of the tape).

As far as I can tell, if the volume was already full, you don't
need to do the padding, as ADSM has already done it. The number
of blocks that ADSM cares about is relative to the start of the
big data file, so if your tape copy utility can be convinced to
copy the blocks at all -- even with media errors -- then AUDIT
VOLUME is usually able to pick up the pieces. SAS's PROC TAPECOPY
seems to work well for this sort of thing, and it's faster than
using DITTO.

One other thing: if you get a readable tape, the first thing you
should do after the AUDIT VOL finishes is do a MOVE DATA to get
the data off that tape and written somewhere else safely. That
may be just paranoia on my part, but it's a good idea none the less.


> [yummmy good stuff about tape formatting]

Thanks for the inside guts on the tapes. That might make it
possible to make a repair utility. Pipelines to the rescue...!