On Sun, Feb 27, 2005 at 11:47:59AM -0800, Scott Ellis wrote:
> I'd like some clarification on the use of fssconfig(8) with FFS.  The usage
> is:
> 
> fssconfig [-cxv] device path backup [cluster [size]]
> 
> What value is the 'backup' argument?

It is a file used as a backing store. You will see it has flags SNAPSHOT
and the size of the snapped file system.

> For example, what is the difference between "fssconfig fss0 / /" and
> "fssconfig fss0 / /.snapshot"?  They both appear to configure a persistent
> snapshot with fss0, and can be mounted anywhere (e.g., "mount /dev/fss0
> /foobar" works, as does "mount /dev/fss0 /.snapshot").

Using a directory means the backing store is unlinked after setup. This type
of snapshot will be deleted when unconfigured or when the snapped file system
is unmounted. Using an explicit file makes the snapshot persistent (live
after unmount).

> Does the 'backup' argument just simply need to be SOMETHING so that fss can
> determine which filesystem the snapshot is for?
> 
> An example of how to configure a snapshot of a filesystem for use with 'tar'
> (or access in a NetApp-style manner) would be most welcome.
> 
> 	ScottE
> 

-- 
Juergen Hannken-Illjes - hannken@eis.cs.tu-bs.de - TU Braunschweig (Germany)