[xubuntu-users] DVD iso burning 8X?

[Steve Litt]

On Mon, 1 Sep 2014 23:52:50 +0100 (BST)
James Freer <jessejazza3.uk at gmail.com> wrote:

> Since I bought a new PC a couple of years ago I haven't been able to
> burn isos and get the correct md5sum. Using both Brasero and k3b the
> min speed this drive can do is 8X. Every time I burn an iso it fails
> the md5sum. I tried DVD-RW 4X discs and that worked - but when I
> blank the disk and try to burn another it fails. It seems I have a
> poor DVD drive - are these modern SATA drives only capable of 8X. It
> plays DVD videos fine and seems to be ok otherwise.
> 
> I understood that the bigger the iso the more likely a burn is to
> fail. How reliable is burning a DVD?
> 
> My old PC only had a CD writer/DVD reader drive bought in 2005 - it's
> been faultless burning CD isos and I have only ever used 4X (it's
> minimum speed). Maybe it's old but never failed to produce a copy.
> 
> This newer PC DVD drive it would seem is poor at 'writing'. I'd be
> grateful if someone could let me know if they've had problems burning
> DVDs at 8X - were CD writers more reliable? I have always burnt an
> iso for each release install as I don't like USB sticks... perhaps
> that's what most folk use now.

It might not be your DVD drive or media at all. It might be an
instrumentation problem: Namely, that your method of getting an md5sum
off the DVD conflicts with the Linux "readahead bug".

See this article:

http://troubleshooters.com/linux/coasterless.htm

It was written 12 years ago, but is still valid. Try the "rawread"
script like this:

./rawread /dev/dvd | md5sum

If nothing else works, here's how I burn a DVD:

wodim dev=/dev/sg(whatever) driveropts=burnfree padsize=63s \
-dao -pad -v -eject /path/to/myfile.iso

The 63s really does help on edge cases.

HTH,

SteveT

Steve Litt                *  http://www.troubleshooters.com/
Troubleshooting Training  *  Human Performance