Interpretation wanted for HDERR code EF:1

[was-John McMillan]

In article <4387 at cbnewsm.ATT.COM> myamin at cbnewsm.ATT.COM (m.yamin) writes:
>Does anyone know what HDERR error flag 1 means?  Here is a specimen
>line from unix.log:
>
>HDERR ST:51 EF:1 CL:4282 CH:4200 SN:4208 SC:4202 SDH:4224 DMACNT:FFFF
>DCRREG:94 MCRREG:8900 Tue Sep 19 20:58:09 1989

	The error means the Data Address Mark was not found.
	The DAM is part of the meta-information written during
	formatting.  It should never be re-written until the next
	formatting.

	A marginal recording of this mark, or a marginal bit
	of surface damage might make this an intermittent error.
	You HAVE NOT mentioned if these errors are logged as
	being on the same cylinder/sector, however, and if there
	is only one damaged sector it's quite possible you could
	on access it intermittently.

	Errors are logged BEFORE they are total.  Preferably
	there'd be a retry-count message alongside, but that
	code was misplaced slightly -- I believe -- causing it to
	not be logged under certain circumstances.  It is
	quite possible you are just having to perform a re-read
	and are therefore NOT losing anything but the spin time.

	The message would disappear if the damaged sector were
	added to your bad block table -- or, probably, if you
	re-format your disk.

john mcmillan	-- att!mtunb!jcm	-- speaking for self, only...