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Date: Wed, 3 Aug 2005 14:51:06 +0200
From: cpghost <cpghost@cordula.ws>
To: Greg 'groggy' Lehey <grog@FreeBSD.org>
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Cc: Jeff Mitchell <skeezix@skeleton.org>, freebsd-questions@freebsd.org
Subject: Re: DVD burning..
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On Tue, Aug 02, 2005 at 10:22:19AM +0930, Greg 'groggy' Lehey wrote:
> of coasters, and it might help identify the issues.  All my burn
> failures (about 40% of total!) have been with DVD+Rs, though
> admittedly a cheap no-name brand bought in Taipei.  I've found that
> they work OK if I burn them at speed=1; if I use the default speed of
> 4, they usually fail.

Same here. DVD+R fail for me at a similar rate, though DVD-R from
the same brand are doing just fine.

What's puzzling is that growisofs doesn't always notice errors
while burning. Approx 1/3rd of errors are first detected while reading
the DVD+R back in (MEDIUM ERROR READ BIG etc..). OTOH, I'm adding and
later checking md5 checksums for every file; and I've never had a
checksum mismatch. If something goes wrong, it's the whole reading of
a sector or a bunch of sectors.

Oh, and this happens with multiple DVD writers on different machines.

Regards,
-cpghost.

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