Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!rochester!rutgers!att!whuts!homxb!antique!cjp
From: cjp@antique.UUCP (Charles Poirier)
Newsgroups: comp.sys.amiga.tech
Subject: Re: st277n drive and sectors per track & cyl
Summary: over 64 sectors: what symptoms?
Message-ID: <2532@antique.UUCP>
Date: 2 Feb 89 19:00:34 GMT
References: <mount> <3836@cs.Buffalo.EDU> <11175@gryphon.COM> <3277@amiga.UUCP>
Reply-To: vax135!cjp (Charles Poirier)
Organization: AT&T Bell Labs, Holmdel, NJ
Lines: 29

In article <3277@amiga.UUCP> kodiak@tooter.UUCP (Robert Burns) writes:
>In article  jdow@gryphon.COM (J. Dow) writes:
>)The proper trick (or at least the easiest) is to tell the mountlist that the
>)drive has only one head and 155 blockspertrack.
>
>That's what I do too ... but please don't use this trick with a 2090 or 2090A,
>because the format command for these is currently limited to 64 sectors per
>track, so you won't be able to format the drive w/ (1, 155) (heads, bpt).
>You have to come up with a heads*bpt*(hicyl-lowcyl+1) that best represents
>your partitioning configuration and respects the 64 bpt limit.  The drive
>should work fine, but you won't be able to access all the sectors with one
>partition.
>-- 
>Bob Burns, amiga!kodiak                   _

Could you elaborate on that please?  How would I know if there was
trouble?  I formatted my Quantum Q280 80-meg HD (using an A2090) as 2
surfaces @ 95 sectors, with one 20 MB OFS partition and a second 60 MB
FFS partition which is about 70% full.  By comparison, 64/95 sectors is
only 67%, so at least I know I'm not wrapping around and overwriting
already-used sectors.  The format command didn't complain.  The only
trouble has been one hard R/W error in a file, discovered while making
an incremental backup.  Is that a symptom of a sector that the format
command missed?

-- 
	Charles Poirier   (decvax,ucbvax,mcnc,attmail)!vax135!cjp

   "Docking complete...       Docking complete...       Docking complete..."