Re: Strange dumps - "file changed as we read it"

On Saturday 04 January 2003 14:15, C. Bensend wrote:
>Hey folks,
>
>       I'm having an odd problem with one of my backup clients.
>Every single night (I back up nightly), one particular partition
>ends up with a "STRANGE" report, saying that a file (pick a file,
>any file) has changed while it was being read.
>
>The stats:
>
>Client:                OpenBSD 3.2-STABLE
>Server:                OpenBSD 3.2-STABLE
>Amanda:                2.4.2p2 from OpenBSD ports tree, -STABLE branch
>Partition:     /mp3, accessible via Samba for my local LAN,
>               mode 0775
>
>       This partition, obviously, holds my MP3's for my listening
>pleasure.  I've gone to an awful lot of work to rip and encode
> these things, so I'd like to make sure they're backed up.  I'm
> just having a hard time figuring out why, on this particular
> partition, every night a "file changed while it was being read."
>
>       Could this be Samba?  The timestamps on said files aren't
>changing.  Last night, the file that "changed" wasn't even being
>accessed - I didn't even have a Windows machine on the LAN!  And
>before you ask, no other machine was accessing it either.  :)
>
>       Thoughts?  While this is just a minor annoyance, it pains me
>to not understand why this is happening.  I'd appreciate any help
>you folks could give me.
>
>Benny

I've been told, and have repeated here, that the mtimes of a file 
are not supported by samba because they are not supported by the 
underlying (usually vfat) file system.  So apparently, some dummy 
value gets plugged into that field, and if it changes, you get the 
message.

If this is not the correct explanation, somebody jump in and bail me 
out here please.

In a roundabout way, this also explains why a samba share will often 
get a level 1 that looks like a level 0 sizewise.  I also have one 
non-samba, small dos partition for holding bios flash images and 
such, and it gets a full every night, apparently for this same 
reason.  Minor detail in that case as its less than 20 megs.

This to me, if its all true, is the one major achilles heel of 
samba.

I keep my music on an ext3 partition :-)

-- 
Cheers, Gene
AMD K6-III@500mhz 320M
Athlon1600XP@1400mhz  512M
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