# USB DVD-RW burns coasters

## jnthornh

After hours of searching and tinkering, I've had no luck tracking down the source of this problem - so I figured I would post it here.

I have an LG USB DVD-RW drive, which is called in the product documentation a "Super Multi DVD recorder."  The model number is GSA-E10L.  According to lsusb, it's: 

```
Bus 001 Device 005: ID 152e:2507 LG (HLDS)
```

.  This is hooked up to my Dell PowerEdge 400SC running Gentoo.

Now, at one point in time, I was able to burn DVDs using mytharchive on this machine.  It was really nifty, and I was happy.

At some point this stopped working.  Even though the device still appears to be functional (and can play back discs), burning via any mechanism (using growisofs directly or mytharchive) always fails.

I assumed it must have just been a problem with the drive or the media, but that seems to be incorrect - I plugged it into my Dell Laptop running Ubuntu and it worked like a champ.  I bought new media to be safe - still no love when hooked up to the gentoo box.

I'm running kernel 2.6.18-gentoo-r2, but I had the same problem with 2.6.17.

Here's what dmesg looks like when I attach the device:

```

usb 1-6: new high speed USB device using ehci_hcd and address 8

usb 1-6: configuration #1 chosen from 1 choice

scsi6 : SCSI emulation for USB Mass Storage devices

usb-storage: device found at 8

usb-storage: waiting for device to settle before scanning

  Vendor: HL-DT-ST  Model: DVDRAM GSA-E10L   Rev: LE05

  Type:   CD-ROM                             ANSI SCSI revision: 00 burns

sr0: scsi3-mmc drive: 125x/125x writer dvd-ram cd/rw xa/form2 cdda tray

sr 6:0:0:0: Attached scsi CD-ROM sr0

sr 6:0:0:0: Attached scsi generic sg2 type 5

usb-storage: device scan complete

```

This shows up whenever a blank disc is inserted - looks rather suspicious, no?

```

end_request: I/O error, dev sr0, sector 0

Buffer I/O error on device sr0, logical block 0

end_request: I/O error, dev sr0, sector 0

Buffer I/O error on device sr0, logical block 0
```

Here's what a failed burn looks like (I am running this as root):

```
mingus work # growisofs -Z /dev/sr0 -V MYDVD -dvd-video dvd

Executing 'mkisofs -V MYDVD -dvd-video dvd | builtin_dd of=/dev/sr0 obs=32k seek=0'

Unknown file type (unallocated) dvd/.. - ignoring and continuing.

/dev/sr0: "Current Write Speed" is 16.4x1352KBps.

:-[ WRITE@LBA=90h failed with SK=5h/ASC=21h/ACQ=02h]: Invalid argument

:-( write failed: Invalid argument

/dev/sr0: flushing cache

/dev/sr0: updating RMA

/dev/sr0: closing disc
```

It sits and spins a while before it decides on "Current Write Speed," but once it reaches that point all of the other text immediately follows.  The drive is spun up and is doing *something* to the disc, as after this completes visually inspecting the disc reveals that it's been burned about 1/3 of the way complete.  Whatever is on there, though, is not readable in any of my drives.

I'm desperate here - any ideas?

----------

## mbjr

Hi,

Can you run: 

```
mkisofs -V MYDVD -dvd-video dvd | builtin_dd of=/dev/sr0 obs=32k seek=0'
```

 and see what the output is? It seems to be failing there, pushing back "unknown" to your growiso.

Cheers,

----------

## jnthornh

That's not an actual problem - growisofs always seems to report that (even when it works).  I don't believe it matters as it passes the dvd-video option to mkisofs.

----------

## mbjr

Hi,

Such can be caused by couple of things.

1) older kernel versions don't allow a write command to execute for longer than 30 secs - what kernel are you using?

2) growisofs allows limit of 3 minutes for command to execute - how much time does it take to get to that error?

3) wrong disk type / poor disk quality maybe?

I guess you didn't have a firmware upgrade on your device, etc.

Cheers,

----------

## jnthornh

Looks like I found the culprit - and it's (probably) not a gentoo specific problem.

I figured that it couldn't be hardware or a media problem, so I started killing processes to find out what might be interfering.  Turns out it was the mythtv transcoding daemon - which, in Gentoo, is started on boot by an init script.

MTD is responsible for ripping DVDs and converting them to other formats.  It seems that it also takes it upon itself to monitor the DVD drive - and that monitoring interrupts burning, leading to a coaster.

----------

