Hi all, I'm having a bit of a problem when creating CD's from ISO images, and I was wondering if somebody could set the record straight. First my setup: I'm running SuSE 7.3 Professional on an Athlon 1.2 GHz, 256 MB RAM, 20 GB hard drive, LiteON IDE DVD-ROM, Plextor IDE PlexWriter 12/10/32A This last two under SCSI emulation, of course: /dev/sr0 (DVD-ROM) /dev/sr1 (PlexWriter) I downloaded FreeBSD 4.5 ISO images. I verified the md5 sums and they are all correct, which tells me, my images are not corrupt. I then burned the CD's using this command: cdrecord -data -eject dev=0,1,0 speed=12 image-name.iso Burning process goes OK. Here comes the 'weird' part; I try to verify my new CD, put it into my DVD drive and issue the following command: cmp image-name.iso /dev/sr0 You can see (and hear) the DVD drive go into action, as well as the hard drive, but after a while, the process ends with an I/O error cmp: /dev/sr0: Input/output error So, I tried the alternative, getting an image with dd and compare the two images: dd if=/dev/sr0 of=new-cd-image.iso ; cmp image-name.iso new-cd-image.iso But dd also terminates with an I/O error. OK so try readcd... no luck, readcd terminates with an I/O error exactly one sector before the last one (I've done this with several CD's and it's always the same). oross@betelguese:~> readcd dev=0,0,0 f=freebsd-4.5-cd1.iso ; cmp 4.5-install.iso freebsd-4.5-cd1.iso Capacity: 319346 Blocks = 638692 kBytes = 623 MBytes = 654 prMB Sectorsize: 2048 Bytes Copy from SCSI (0,0,0) disk to file 'freebsd-4.5-cd1.iso' end: 319346 readcd: Input/output error. read_g1: scsi sendcmd: no error CDB: 28 00 00 04 DF 00 00 00 72 00 status: 0x2 (CHECK CONDITION) Sense Bytes: 70 00 25 00 00 00 00 0A 00 00 00 00 64 00 00 00 Sense Key: 0x5 Illegal Request, Segment 0 Sense Code: 0x64 Qual 0x00 (illegal mode for this track) Fru 0x0 Sense flags: Blk 0 (not valid) illegal block length cmd finished after 0.326s timeout 40s readcd: Input/output error. Cannot read source disk readcd: Retrying from sector 319232. ..................................................................................................................~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~+~~~-~~~ readcd: Input/output error. Error on sector 319345 not corrected. Total of 1 errors. Time total: 343.373sec Read 638464.00 kB at 1859.4 kB/sec. cmp: EOF on freebsd-4.5-cd1.iso The CD works OK (at least apparently), I installed FreeBSD from it on a test machine. But this problem was bugging me. I tried different brand CD-R's, tried also CD-RW's, different burning speeds.... nothing. Then, I tried verifying the discs using the Plextor, not the LiteON.... wow!! it works!!! just a direct cmp works!! cmp 4.5-install.iso /dev/sr1 dd also works, as well as readcd!! Still, I don't like the idea of using my writer as a reader, I've heard, this shortens the life of my writer quite a bit. I must say my DVD drive performs perfectly in all other respects (playing DVD's, audio CD's, ripping, etc) So, questions. Is this normal behavior? Can I only verify CD's in a CD-RW drive? (I'd obviously say no!) Or is it just my DVD drive that is not working correctly? Is that the correct cdrecord commmand for burning ISO images? And last, a bit of an 'out' question How can I tell if cdrecord is using my drive's Burn Proof feature? Thanks all in advance Oscar Ross