differences in supported filesystems between FreeBSD versions

[RW]

On Friday 12 August 2005 18:30, Gary W. Swearingen wrote:
> Dmitry Mityugov <dmitry.mityugov at gmail.com> writes:
> > I am not sure how safe it is. Is it safe to use a HDD partitioned and
> > formatted by one version of FreeBSD with a newer version? I know there
>
> I recently ran into the problem of not being able to access 5.x file
> systems and 5.x backups from a 4.x system. (5.2+ and 4.7 & 4.8, IIRC.)

That's the other way around where, where an old OS can't read a new partition. 

I don't think a change in filesystem, would ever be made without support for 
the old version being provided - at very least as a kernel option. For 
example COMPAT_FREEBSD4 provides access to filesystems created in version 4 
and early releases of 5.x, and it's compiled into  the 5.4 generic kernel by 
default.