: does the above message mean that the cdrom (the disk, not the drive)
: is defective ?
: I get a lot of this messages after dd if=/dev/scd0 of=/dev/null:
: scsi0 channel 0 : resetting for second half of retries.
: SCSI bus is being reset for host 0 channel 0.
: SCSI CD error : host 0 id 4 lun 0 return code = 18000002
: Current error sr0b:00: sense key Medium Error
: Additional sense indicates Random positioning error
: CD-ROM I/O error: dev 0b:00, sector 843136
: scsi0 channel 0 : resetting for second half of retries.
: SCSI bus is being reset for host 0 channel 0.
: SCSI CD error : host 0 id 4 lun 0 return code = 18000002
: Current error sr0b:00: sense key Medium Error
: Additional sense indicates Random positioning error
: CD-ROM I/O error: dev 0b:00, sector 843138
: the bad thing is that I cannot ^C the process doing dd nor kill -9 it,
: so it's stuck somewhere in the kernel. or do you have to wait for
: some minutes ? (sync, df will hang from now on...)
Probably you simply reached "end of medium" (about 400 MB size?).
With SCSI drives, the drivers can't recover from that read-ahead-
into-the-unformatted-section-error.
A SCSI specification and/or driver bug, in effect under Linux since
about 1.2.5.
With other CDROM drivers, the read request returns a "fail" to the
higher level (ll_rw_blk), and there is an error counter.
Cheers -e
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