What is this mega-dvd-test?

[Robert G. (Doc) Savage]

On Sun, 2010-10-31 at 19:03 -0600, Stephen John Smoogen wrote:
> On Sun, Oct 31, 2010 at 16:33, Robert G. (Doc) Savage
> <dsavage at peaknet.net> wrote:
> 
> > Bruno,
> >
> > I think I found at least part of the problem here. The Downloads
> > directory in my home folder is bind mounted to an NFS filesystem on an
> > RHEL5 server. For some reason the iso file is being severely truncated
> > by that NFS filesystem:
> >
> > Here's the original file in a 1.1TB ext3 filesystem:
> >
> >        Red Hat Enterprise Linux Server release 5.5 (Tikanga)
> >        Sunday - October 31, 2010  17:16:56 CDT
> >        [doc at lion] /pub/fedora/linux/releases/14/Live
> >        $ ls -l
> >        total 5463812
> >        -rw------- 1 doc doc        950 Oct 21 09:17 Fedora-14-Live-multi-CHECKSUM
> >        -rw------- 1 doc doc 5589458944 Oct 21 10:06 Fedora-14-Live-multi.iso
> >        drwxrwxr-x 2 doc doc       4096 Oct 26 20:02 i386
> >        drwxrwxr-x 2 doc doc       4096 Oct 26 20:02 x86_64
> >
> > Here's the NFS-exported version as seen on the F13 system, the one
> > running l-i-t-d:
> >
> >        Fedora release 13 (Goddard)
> >        Sunday - October 31, 2010  16:55:17 CDT
> >        [doc at tiger] /net/lion/pub/fedora/linux/releases/14/Live
> >        $ ls -l
> >        total 5463812
> >        -rw------- 1 doc doc        950 Oct 21 09:17 Fedora-14-Live-multi-CHECKSUM
> >        -rw------- 1 doc doc 1294491648 Oct 21 10:06 Fedora-14-Live-multi.iso
> >        drwxrwxr-x 2 doc doc       4096 Oct 26 20:02 i386
> >        drwxrwxr-x 2 doc doc       4096 Oct 26 20:02 x86_64
> >
> > Curiously, the difference in file sizes is precisely 4GB. Is this a bug,
> > or normal behavior for NFS?
> 
> Possibly a bug, depends on if the RHEL server is 64 bit or not, and
> you are using NFSv3 (and in TCP). It supposedly works in UDP but I
> have had problems myself with large files like that.

Stephen,

64-bit NFSv3 on the RHEL5 server. Using 64-bit NFSv4 and autofs on the
F13 side. The latter makes things easy, but completely obscures my
ability to troubleshoot. ("You don't need to know those things...")

--Doc Savage
  Fairview Heights, IL