DOS feature on formatting disk

From: Paul Koning <pkoning_at_equallogic.com>
Date: Wed Jan 19 10:39:41 2005

>>>>> "Bj??rn" == Bj??rn Vermo <bv_at_norbionics.com> writes:

 Bj??rn> On Tue, 18 Jan 2005 09:35:01 -0800 (PST), Dwight K. Elvey
 Bj??rn> <dwight.elvey_at_amd.com> wrote:

>> Hi DOS has an irritating feature when asked to format a disk. If
>> track 0 is partially readable it will fail to format, even if you
>> use the /u option. I've been moving data from one machine to
>> another and the source machine has a flaky drive. It sometimes
>> trashes track 0.
 Bj??rn> ...

 Bj??rn> Any OS / file system has problems if track 0 is really bad,
 Bj??rn> especially if sector 0 is bad.

That's definitely not true. For example, PDP11s use sector 0 for the
boot sector, bot not for anything else. A disk that doesn't need to
be booted will work perfectly well with an unreadable sector 0.
Depending on the OS, there may be some other critical sector (sector 1
on RSTS, for example). More sophisticated file structures have a
search rule, where the "superblock" can be found in one of several
places that are checked in order.

       paul
Received on Wed Jan 19 2005 - 10:39:41 GMT

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