Since 5 Years we have used DVD-RAMs for regulary backups without any problems. But now formatting new DVD-RAMs and writing to previously formatted DVD-RAMs does not work any more and results in an unmountable medium. Mounting and reading older DVD-RAMS still works.

To prepare DVDRAMS for writing we do the following commands:

[act@ft--fhs-u3] ~>sudo pktsetup dvdram /dev/sr0

[act@ft--fhs-u3] ~>sudo chgrp cdrom /dev/pktcdvd/dvdram

[act@ft--fhs-u3] ~>sudo chmod g+rw /dev/pktcdvd/dvdram

[act@ft--fhs-u3] ~>mkudffs --media-type=dvdram --vid="test1" --lvid="test1" /dev/pktcdvd/dvdram
start=0, blocks=16, type=RESERVED
start=16, blocks=3, type=VRS
start=19, blocks=237, type=USPACE
start=256, blocks=1, type=ANCHOR
start=257, blocks=16, type=PVDS
start=273, blocks=1, type=LVID
start=274, blocks=2236172, type=PSPACE
start=2236446, blocks=1, type=ANCHOR
start=2236447, blocks=239, type=USPACE
start=2236686, blocks=16, type=RVDS
start=2236702, blocks=1, type=ANCHOR

[act@ft--fhs-u3] ~> cat /etc/fstab
...
/dev/pktcdvd/dvdram /dvdram udf noauto,rw,user,owner,noatime,async 0 0
...


[act@ft--fhs-u3] ~>mount /dvdram
mount: wrong fs type, bad option, bad superblock on /dev/pktcdvd/dvdram,
missing codepage or helper program, or other error

In some cases useful info is found in syslog - try
dmesg | tail or so.

[act@ft--fhs-u3] ~>dmesg
...
[ 194.580528] pktcdvd: writer pktcdvd0 mapped to sr0
[ 217.752066] pktcdvd: write caching control failed
[ 217.752070] pktcdvd: 55 10 00 00 00 00 00 00 14 00 00 00 - sense 00.00.00 (No sense)
[ 217.754361] pktcdvd: write speed 4155kB/s
[ 222.590094] pktcdvd: 4473406kB available on disc
[ 226.840141] attempt to access beyond end of device
[ 226.840149] sr0: rw=0, want=8946816, limit=8946812
[ 267.248762] pktcdvd: write caching control failed
[ 267.248766] pktcdvd: 55 10 00 00 00 00 00 00 14 00 00 00 - sense 00.00.00 (No sense)
[ 267.251265] pktcdvd: write speed 4155kB/s
[ 267.315836] pktcdvd: 4473406kB available on disc
[ 267.391754] UDF-fs: warning (device pktcdvd0): udf_load_vrs: No VRS found
[ 267.391758] UDF-fs: warning (device pktcdvd0): udf_fill_super: No partition found (2)



If inserting an older written DVDRAM mounting still works:
[act@ft--fhs-u3] ~>mount /dvdram
[act@ft--fhs-u3] ~>dmesg
...
[ 961.238477] pktcdvd: write caching control failed
[ 961.238482] pktcdvd: 55 10 00 00 00 00 00 00 14 00 00 00 - sense 00.00.00 (No sense)
[ 961.240761] pktcdvd: write speed 4155kB/s
[ 966.731445] pktcdvd: 4473406kB available on disc
[ 966.877761] UDF-fs: INFO Mounting volume 'ACT/FHS Backup Disk 71', timestamp 2013/12/17 15:14 (1078)

[act@ft--fhs-u3] ~>uname -a
Linux ft--fhs-u3 3.11.10-17-default #1 SMP Mon Jun 16 15:28:13 UTC 2014 (fba7c1f) x86_64 x86_64 x86_64 GNU/Linux

My guess ist, that an os/kernal update has changed something to the dvd-ram drivers, but I am unable to figure it out or find a solution to get it to work again.
In the first week of January everything worked fine, so the "bad" update must have been installed in the last 6 month. We have also tried to burn DVDRAMs on an other linux machine with the same error, so I am confident, that the hardware is ok.

If someone could help me to solve this problem, it would make me happy.

Thanks in advance,

Matthias

I'd suspect the burn laser is bad.

Boot to some live usb or toram option and see if you can burn some disc.

Last choice is the disc. One of the three has to be the issue.

If you can boot to a live media or older kernel then see what all is being loaded. Then compare it to current system.

Even though you say that it happens on more than one machine, I would still suspect the drive(s) itself.

CD/DVD recorders have been by far the single most unreliable hardware device I have encountered (in fact, I replaced yet another one yesterday...). Thay almost always fail to write but are still able to read, or lose the ability to read recorded media while still reading pre-manufactured media.

If it is multiple machines of similar age and history, multiple failures within the same six month period would be common as well in my experience.

If you want to explore the possibility of a kernel update related issue it would be helpful to know the distro and update history.

mke2fs -b 2048 /dev/scd0 (put your device in) should burn to a dvd-ram.


http://tr.opensuse.org/SDB:Burning_DVDs_with_SuSE_Linux

Hi,

We have made more tests whicht confirmed to 100%, that the hardware is ok:
First we have tried burning DVD-RAMs on 2 more machines (total 4), always with the same error. Then we have removed the DVD-RAM drive and build it in another machine with an older kernel. There DVD-RAM-burning worked without a problem.

The distribution is: OpenSuse 13.1 "bottle" with kernel 3.11.10-17-default
Please tell me, if you need more information.
To the update history I can say that our admin has regulary updated the system, but I cannot say which exact kernel versions we have used previously.

Regards,

Matthias Bodenstein

In my experience, It is _very_hard_ to eliminate hardware in this scenario. The standard CD head has a couple of very fine adjustments factory set and sealed, but capable of drifting over time, because the components change. The forward drop on the diodes changes over time, that's for sure, and that affects current flows. I was a hiotline for Welltech

So in the 'iffy' state, the colour of the disk from the exact angles used matters hugely. The drives become temperature sensitive. Running hdparm -Tt on the drive a few times can make a bad disk work (or not work). If that happens, it IS hardware.

There is equipment to reset the things, but it's expensive, and a time consuming operation which is never viable today.

It's easy enough to test an older distro and see if you can get it to work. Did you try the test I suggested?

Since you did this "Then we have removed the DVD-RAM drive and build it in another machine with an older kernel. There DVD-RAM-burning worked without a problem." I assume it should work in other hardware but still many variables exist.

Boot the suspect system to a usb flash drive.

I don't doubt it is the older kernel or associated files or supporting files at all. Just prove it. Then find out what has changed.