On Sun, 11 Jul 1999, Douglas Gilbert wrote: > If you wish to take a closer look at what is happening then perhaps you > could download the utilities tarball at: http://www.torque.net/sg > > You will need to have the sg device driver available (either built into > the kernel or as a module). Then try: sg_readcap /dev/sr0 [or /dev/sr1] > > to see what your block size is and the address of the last block. For > example, if your block size is 2048 and the last block address is > 332529 then try: sg_dd2048 if=/dev/sgc of=/dev/null skip=332529 count=1 > > This utility is just like "dd" but will report any SCSI error directly > to you (and bypasses the cdrom code). This example assumes the sg device > /dev/sgc is the same as the cdrom driver you wish to test. Sg devices > are allocated in the same number and order seen in 'cat /proc/scsi/scsi'. > > Such a test works ok for CDRs burnt on my Yamaha 4416S by cdrecord. > However a friend who uses similar hardware and NT to burn CDRs always > seems to get an error on the last block just as you seem to. However > those CDRs give a "L-EC UNCORRECTABLE ERROR" error which is different > from your report. > > Also the position of the error you have reported is awfully close to > the 650 MB limit for a CDR. Hello ! Thanks for the answers. I tried the sg utilities and attached some of your suggested outputs. As your can see, it works perfectly on my CD-Writer. The Problem is, that the read with dd from the normal CD device (drivers) does not work. Here it fails to read a whole 7 sectors, not only 2 (which seems to be normal and would be taken care of the CD device driver! This means a serious data loss. The read with sg_dd2048 works perfectly. When I try to access the last file on the CD normal with mounting the CD all works perfectly. This seems really strange to me, because I thought, that the file-system reads via the normal CD device drivers which dd uses too. Any further ideas ?! Best regards Sven -- >>> "I am the embodiment of modern medicine." <<<<<<< Der Dativ ist dem <<<<<<< >>>>>> The holographic doctor, USS-Voyager <<<<<<<<<< Genitiv sein Tod. <<<<<<< >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< >> http://www.fmi.uni-passau.de/~anderss >< email: [EMAIL PROTECTED] <<
========================================================================= On my DVD-ROM: -------------- > dd if=/dev/scd0 of=test.iso count=308112 bs=2048 dd: /dev/scd0: Input/output error 308105+0 records in 308105+0 records out > ll test.iso -rw-rw-r-- 1 anderss users 630999040 Jul 13 00:04 test.iso > mount -t iso9660 -o loop test.iso /mnt > cat /mnt/mr_president-night-club/night-club.txt cat: /mnt/mr_president-night-club/night-club.txt: Input/output error in /var/log/messages: --------------------- Jul 13 00:44:11 skeeve vmunix: attempt to access beyond end of device Jul 13 00:44:11 skeeve vmunix: 07:00: rw=0, want=616222, limit=616210 Jul 13 00:44:11 skeeve vmunix: dev 07:00 blksize=2048 blocknr=308110 sector=1232440 size=2048 count=1 ------------------------------------------------------------------------- > sg_readcap /dev/sr0 >>> Mapping /dev/sr0 to sg device: /dev/sg1 Read Capacity results: Last block address = 308113 (0x4b391), Number of blocks = 308114 Block size = 2048 bytes ------------------------------------------------------------------------- > sg_dd2048 if=/dev/sg1 of=xxx skip=308113 count=1 reading: Check Condition Info fld=0x4b391, Current sense key: Medium Error Additional sense indicates: Circ unrecovered error Raw sense data: 0xf0 0x00 0x03 0x00 0x04 0xb3 0x91 0x0a 0x00 0x00 0x00 0x00 0x11 0x06 0x00 0x00 plus...: Driver_status=0x28 (DRIVER_SENSE,SUGGEST_ABORT) sg_read failed, skip=308113 Some error occurred, count=1 ------------------------------------------------------------------------- > sg_dd2048 if=/dev/sg1 of=xxx skip=308112 count=1 reading: Check Condition [valid=0] Info fld=0x0, Current sense key: Illegal Request Additional sense indicates: Illegal mode for this track Raw sense data: 0x70 0x00 0x05 0x00 0x00 0x00 0x00 0x0a 0x00 0x00 0x00 0x00 0x64 0x00 0x00 0x00 plus...: Driver_status=0x28 (DRIVER_SENSE,SUGGEST_ABORT) sg_read failed, skip=308112 Some error occurred, count=1 ------------------------------------------------------------------------- > sg_dd2048 if=/dev/sg1 of=xxx skip=308111 count=1 1+0 records in 1+0 records out ========================================================================= Second try with the sg utilities: --------------------------------- > /public/sbin/sg_dd2048 if=/dev/sg1 of=test.img count=308112 308112+0 records in 308112+0 records out > ll test.iso -rw-rw-r-- 1 anderss users 631013376 Jul 13 00:39 test.iso > mount -t iso9660 -o loop test.iso /mnt > cat /mnt/mr_president-night-club/TRANS.TBL F NIGHT-CL.000;1 night-club.13.mp2 [here comes the full file]... in /var/log/messages: --------------------- [None] ========================================================================= Normal mount on the DVD-ROM: ---------------------------- > mount -t iso9660 /dev/scd0 /mnt mount: block device /dev/scd0 is write-protected, mounting read-only > cat /mnt/mr_president-night-club/TRANS.TBL F NIGHT-CL.000;1 night-club.13.mp2 [here comes the full file]... in /var/log/messages: --------------------- Jul 13 01:05:36 skeeve vmunix: ISO 9660 Extensions: RRIP_1991A ========================================================================= On my CD-ROM: ------------- > dd if=/dev/scd1 of=test.iso count=308112 bs=2048 308112+0 records in 308112+0 records out > ll test.iso -rw-rw-r-- 1 anderss users 631013376 Jul 13 00:39 test.iso > mount -t iso9660 -o loop test.iso /mnt > cat /mnt/mr_president-night-club/TRANS.TBL F NIGHT-CL.000;1 night-club.13.mp2 [here comes the full file]... in /var/log/messages: --------------------- [None]
