FreeBSD 11 and 4+ GB files on optical disc

David Christensen dpchrist at
Fri Feb 10 01:51:36 UTC 2017

On 02/09/17 15:55, Polytropon wrote:

Thanks for the reply.

> On Thu, 9 Feb 2017 15:04:13 -0800, David Christensen wrote:
>> I periodically create archive files on Debian 7, encrypt the archive,
>> create checksum files, burn the archive and checksum files to optical
>> disc, and then verify the contents of the disc.
> So I can assume you're using ISO-9660 as the file system for
> the optical disc - a very important aspect you never mentioned. :-)

dpchrist at freebsd:/usr/home/dpchrist $ mount | grep /dev/cd0
/dev/cd0 on /media/HOLGERDANSKE_COM (cd9660, local, nosuid, read-only)

>> I suspect that FreeBSD is having problems because the archive file is
>> larger than 4 GB (?).
> Well, if you accurately consider the file size conversion ...
> Check what the file system specification says ...
> So what you're seeing (file appearing twice) exactly matches
> the assumption that mkisofs is creating a "split entry" for a
> source file that the ISO-9660 file system cannot contain due
> to a size limitation.

I created the disc on Linux, and have been creating discs just like it 
for several years.  I guess Linux hides the "split entries"; it "just 

When I browse the disc using Vista 32-bit, Windows Explorer shows the 
files on the disc correctly.

> Don't use ISO-9660. Use tar as a file system (or better, instead
> of a file system). You can write it to the DVD like this:
> 	% growisofs -dvd-compat -Z /dev/dvd=2017.01.tar
> And read (restore) it like this:
> 	% tar xvf /dev/dvd
> The advantage: No size limitation imposed by ISO-9660.Additional security: "There are no files on the DVD!" ;-)

That is not security; that is incompatibility.

This is an archive disc.  I have created many such discs over the years. 
  I need to be able to browse and read them on as many platforms as 

How do I browse and read 4+ GB files on optical discs (DVD, BD) 
correctly on FreeBSD?


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