samba - Nov 2011 - What could cause the streams depot to become confused?

I'm using a program on Windows Server 2008 R2 x64 that requires NTFS
alternate data streams. It's talking to a Samba 3.6.0 SMB2 share configured
with streams_depot. The program has been running for over a month with no
obvious problems, except that the filesystem has been accumulating
"lost" directories. Apparently, at some point after the whole server
crashed (both are VMs running on this server), the program can't seem to
access any stream data. What could be causing this?

What could the program, which is the only user who has access to this ZFS
filesystem, be doing that it causes Samba to generate "lost"
directories? Could this have anything to do with the present situation?

The code for the streams module says it generates hashes from the
"fsid," but it's not clear where this number comes from? The samba
server is replicated to another server using ZFS send/receive and the filesystem
and program were originally accessing the streams data from the original server
and then at some point later were switched to using the replicated filesystem.
However, that was weeks ago and there wasn't any problem until very
recently.

Is there any way to debug what might be going on? Is there any easy way to test
if the stream depot can retrieve streams?

On Thu, Nov 03, 2011 at 04:18:23AM +0000, Maurice R Volaski
wrote:
> I'm using a program on Windows Server 2008 R2 x64 that
> requires NTFS alternate data streams. It's talking to a
> Samba 3.6.0 SMB2 share configured with streams_depot. The
> program has been running for over a month with no obvious
> problems, except that the filesystem has been accumulating
> "lost" directories. Apparently, at some point after the
> whole server crashed (both are VMs running on this
> server), the program can't seem to access any stream data.
> What could be causing this?
> 
> What could the program, which is the only user who has
> access to this ZFS filesystem, be doing that it causes
> Samba to generate "lost" directories? Could this have
> anything to do with the present situation?
> 
> The code for the streams module says it generates hashes
> from the "fsid," but it's not clear where this number
> comes from? The samba server is replicated to another
> server using ZFS send/receive and the filesystem and
> program were originally accessing the streams data from
> the original server and then at some point later were
> switched to using the replicated filesystem. However, that
> was weeks ago and there wasn't any problem until very
> recently.
> 
> Is there any way to debug what might be going on? Is there
> any easy way to test if the stream depot can retrieve
> streams?
The depot module depends on the device number being
consistent. If you issue a "stat <filename>" you can see the
device number. If that changes for the base files, then the
attached streams become inaccessible.

Volker

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