bad block bug on second disk in V/AT 2.4.0L

[Paul De Bra]

In article <433 at siswat.UUCP> buck at siswat.UUCP (A. Lester Buck) writes:
}Some time ago I asked the net about a weird problem I was having with
}the following setup:
}
}    Microport System V/AT 2.4.0L
}    Adaptec 2372 disk controller
}    Seagate 277R - disk 0
}    Mitsubishi 535 - disk 1
}
[ most of explanation about bad sectors deleted ]
}
}The Microport 2.4 disk driver appartently does full track caching on any
}access to a track, so the message appears for the one bad sector if
}any of that track's sectors are read.  Also, once that track is in
}the track cache, further reads from that track might NOT give the
}console message if they do not access the one bad sector...

Are you sure about this? This would make uPort the first Unix System i've
come accross that would do track buffering.
It may be possible (I don't know the 2372) that it's the Adaptec controller
which does the full track buffering, and it could signal the kernel that
there was an I/O error if any of the sectors on a track is bad.
There are several controllers on the market that do full track buffering.

I believe that with Xenix (and i think also with AT&T wVr3.2)
whole tracks are mapped out if they contain a bad sector.
Your problem indicates that this is indeed a better approach, and well
worth losing a few extra sectors.

Paul.
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