On Fri, Oct 20, 2006 at 01:37:05PM -0700, Jason Thorpe wrote:
> >>  . compatibility/upgrade issues, such as whether the accessing
> >>    filesystem code has to be journal aware, even if the filesystem
> >>    was cleanly unmounted.
> 
> Journaled UFS should get a new magic number.  Old tools will refuse to talk to 
> one in that case.

Even if the filesystem is unmounted clenaly (does not need log recovery)?
Disallowing access by old tools would be suboptimal in this case.

Pavel