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Date: Mon, 8 Oct 2012 11:33:41 +0200
From: Fabian Keil <freebsd-listen@fabiankeil.de>
To: Warren Block <wblock@wonkity.com>
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Cc: freebsd-questions@freebsd.org
Subject: Re: DVD OPC errors with growisofs
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Warren Block <wblock@wonkity.com> wrote:

> I'm using growisofs to write DVDs of backup files.  Some combinations of=
=20
> older drives and newer media give ":-( unable to PERFORM OPC:=20
> Input/output error".

If you are concerned about this, you could try cdrecord
to see if it makes a difference.
=20
> Can limiting write speed avoid these errors?

That depends on both the drive and the media.
It's also possible that it makes matters worse, though.

It's a myth that reducing speed guarantees better results.

>                                               And what ways are there to=
=20
> detect the fastest speed supported by both drive and media?

The drive is supposed to figure it out on its own.

If your drive supports it, you can use readcd to measure how
well burned media can be read and do a couple of experiments
with various burn speeds to see if it affects the results for
your drives and the media you care about.

Fabian

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