Re: Versioning file system

[H. Peter Anvin]

Trond Myklebust wrote:
>>
>> I assume NetApp flags the directory specially so that a POSIX directory 
>> read doesn't get it.  I've seen that done elsewhere.
> 
> No. The directory is quite visible with a standard 'ls -a'. Instead,
> they simply mark it as a separate volume/filesystem: i.e. the fsid
> differs when you call stat(). The whole thing ends up acting rather like
> our bind mounts.
> It means that you avoid all those nasty user issues where people try to
> hard link to/from .snapshot directories, rename files across snapshot
> boundaries, etc.
> 

Last I used a Netapp, it was configurable, I believe; I seem to also
vaguely remember that one could configure it so that it only was
accessible as part of a mount string rather than as part of an
already-mounted filesystem.  Of course, this was a long time ago.

	-hpa
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/