Hi,
I am using cdrecord 1.6.1 on slackware 3.6.
I am burning to the cd data streams directly, not filesystems, for back up
purposes. I write a header at the beginning of each archive with ojnfo
about size etc. so that I can search through the disk later on for the
archives I want to recover. My problem is that although cdrecrod works
fine in writing the tracks, I can't access anything beyond the first
track, e.g. using dd.
For example, here is what should be on the disk:
# cdrecord dev=2,0 -toc
[... deleted stuff ...]
first: 1 last 5
track: 1 lba: 0 ( 0) 00:02:00 adr: 1 control: 4 mode: 1
track: 2 lba: 19563 ( 78252) 04:22:63 adr: 1 control: 4 mode: 1
track: 3 lba: 44156 ( 176624) 09:50:56 adr: 1 control: 4 mode: 1
track: 4 lba: 51358 ( 205432) 11:26:58 adr: 1 control: 4 mode: 1
track: 5 lba: 58702 ( 234808) 13:04:52 adr: 1 control: 4 mode: 1
track:lout lba: 59146 ( 236584) 13:10:46 adr: 1 control: 4 mode: -1
Here is how I can get the header which starts the first archive:
# dd if=/dev/scd0 ibs=512 count=1
Bytestream by backburner, raw stream begins after this 512 byte header
MediaID=938086392 ArchiveID=homecarladambackup.tar.bz2-FULL MediaNum=1
MediaCap=642998272 MediaLen=16712669 LastMedia=1 Device=cdr ---End of
Header---
1+0 records in
1+0 records out
The MediaLen fields tells me how many bytes the archives contains. With
this information I can extract the archive with dd and un-bzip2 and untar
it with no problem. But if I try to read the next header:
# dd if=/dev/scd0 ibs=512 count=1 skip=32644
dd: /dev/scd0: I/O error
0+0 records in
0+0 records out
I even tried to read the whole cd into one file to inspect it later but it
gives the same I/O error at the same point. When this happens here is what
appears in the logs:
Sep 29 10:19:57 wallace kernel: CD-ROM I/O error: dev 0b:00, sector 32644
Sep 29 10:19:57 wallace kernel: scsi0: MEDIUM ERROR on channel 0, id 2,
lun 0, CDB: Read (6) 00 7f 88 1c 00
Sep 29 10:19:57 wallace kernel: Current error sr0b:00: sense key Medium
Error
Sep 29 10:19:57 wallace kernel: Additional sense indicates No reference
position found
Sep 29 10:19:57 wallace kernel: CD-ROM I/O error: dev 0b:00, sector 32648
Sep 29 10:19:59 wallace kernel: scsi0: MEDIUM ERROR on channel 0, id 2,
lun 0, CDB: Read (6) 00 7f 8c 18 00
Sep 29 10:19:59 wallace kernel: Current error sr0b:00: sense key Medium
Error
Sep 29 10:19:59 wallace kernel: CD-ROM I/O error: dev 0b:00, sector 32652
Sep 29 10:20:06 wallace kernel: CD-ROM error: Current error sr0b:00: sense
key Illegal Request
Sep 29 10:20:06 wallace kernel: Additional sense indicates End of user
area encountered on this track
Sep 29 10:20:06 wallace kernel: command was: Read (6) 00 7f 90 14 00
Sep 29 10:20:06 wallace kernel: CD-ROM I/O error: dev 0b:00, sector 32656
I gather I don't understand how to move around cds.
Any help will be greatly appreciated,
thanks,
Stefano
--
Stefano Ghirlanda, Zoologiska Institutionen, Stockholms Universitet
Office: D554, Arrheniusv. 14, S-106 91 Stockholm, Sweden
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