anyone else having mediacheck problems with FC3t1 images?

[John Reiser]

> <3>Buffer I/O error on device hdd, logical block 161345
> <4>hdd: media error (bad sector): status=0x51 { DriveReady SeekComplete 
> Error }
> <4>hdd: media error (bad sector): errir=0x30
> <4>end_request: I/O error, dev hdd, sector 1290776
> 
> There are several more of these type messages each with the logical 
> block and sector incremented by one.

Assume this is FC3-test1-i386-disc1.iso, whose length is 660889600 bytes.
[If it is really -disc2.iso, with length 669511680 bytes, then the
entire rest of _this_ message DOES NOT APPLY.]

Look at this section of "od -c -Ax FC3-test1-i386-disc1.iso  |  more",
which occurs within the first couple screenfuls:
-----
008370 360 001  \0   I   S   O       M   D   5   S   U   M       =
008380   d   0   2   d   d   a   d   1   2   8   4   b   b   9   1   4
008390   3   f   2   9   2   c   6   4   0   e   b   4   b   6   b   8
0083a0   ;   S   K   I   P   S   E   C   T   O   R   S       =       1
0083b0   5   ;   R   H   L   I   S   O   S   T   A   T   U   S   =   0
0083c0   ;   T   H   I   S       I   S       N   O   T       T   H   E
0083d0       S   A   M   E       A   S       R   U   N   N   I   N   G
0083e0       M   D   5   S   U   M       O   N       T   H   I   S
0083f0   I   S   O   !   !
-----
Notice the "SKIPSECTORS = 15;" which [probably] means that the last 15
<somethings> (either IDE 512-byte disk sectors, or 2K-byte CD-ROM physical
blocks) should not be included in the _internal_ md5sum (which is not
the same as the md5sum of the whole .iso file).  This is from the "-pad"
commandline argument to mkisofs.

 From the last console message: Assume "sector 1290776" means "IDE 512-byte
sector 1290776".  Then 1290776 corresponds to byte 1290776 * 512 =
660,877,312, which is 12,288 bytes short of the end of the .iso file.
That 12,288 bytes is within the 15 * 2048 byte -pad region.  So probably
that particular error can be ignored, on the basis that the error arose
by reading beyond the physical end of data, when mediacheck was reading
30 * 2K bytes at a time as an efficiency hack.  The blocks that correspond
to the data that the installer will use, should be OK.

I don't know how to interpret "<3>Buffer I/O error on device hdd,
logical block 161345" which may be from much earlier, or even from
a different CD-ROM.

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