[Vox-Outreach] Testing of CD Images

[Michael Wenk]

On Monday 12 May 2003 01:56 pm, Peter Jay Salzman wrote:
> On Mon 12 May 03,  4:47 PM, Mike Simons <msimons@moria.simons-clan.com> 
opined:
> > [perhaps we should move this to vox-tech]
> >
> > On Mon, May 12, 2003 at 01:31:45PM -0700, Peter Jay Salzman wrote:
> > > point of reference - the only time i've *ever* burned coasters is when
> > > i played a game like quake3 while writing a cd.  other than that, i've
> > > had a 0% failure rate.
> > >
> > > On Mon 12 May 03,  4:25 PM, Mike Simons <msimons@moria.simons-clan.com> 
opined:
> > > >   I would prefer the disks be verified before the event...
> > >
> > > you don't even have to verify it.  just:
> > >
> > >    mount /cdrom; umount /cdrom
> > >
> > > and getting a prompt back quickly is enough.
> >
> > - Could you explain how getting a prompt back quickly means that the
> >   disk image is correctly burned?
>
> sure, it's easy.
>
> i found that the vast majority of burns are either all or nothing.  if
> the burn failed, it's *very* rare the cd will mount.
>
> is it 100% foolproof?  no.  nothing is.
>
> however, i have extensive experience with my own and other peoples' cd
> writers, and when i say "vast majority", i mean exactly that: "vast
> majority".
>
> in fact, i believe the only time i've seen anything to the contrary of
> this, it was with cases of extreme overburning.
>
> and if we're talking about 20 or even 50 burns, using something like
> md5sum is just fscking obnoxious.
>
> pete

When I have a fail, I go ahead and try to mount it.  about 3 times out of 5, 
it will mount properly.  95% of my fails will not boot.  For the ones that do 
not, I try to cdrecord back to em, and normally it just spits em out as 
already being fixated.  I had one that I considered fail boot, and wouldn't 
load the index page.  When I mounted it under linux, the index page was all 
NULLS.  The reason I do this is I noticed once, that I tried to test a blank 
accidentally, and well, it was blank.  



-- 
wenk@praxis.homedns.org
Mike Wenk