Re: FFSv2 vs FFSv1

[Adrian Steinmann <ast%NetBSD.org@localhost>]

On Sun, May 05, 2013 at 05:08:23PM +0900, Ryo ONODERA wrote:
> From: Ray Phillips <r.phillips%uq.edu.au@localhost>, Date: Sun, 5 May 2013 
> 18:02:43 +1000
> 
> > What's the most convenient way of seeing if an existing partition is
> > FFSv1 or v2?
> 
> # file -s /dev/rwd0e
> /dev/rwd0e: Unix Fast File system [v2] (little-endian) last mounted on /usr, 
> last written at Sun May  5 08:05:50 2013, clean flag 2, readonly flag 0, 
> number of blocks 20480040, number of data blocks 19855038, number of cylinder 
> groups 217, block size 16384, fragment size 2048, average file size 16384, 
> average number of files in dir 64, pending blocks to free 0, pending inodes 
> to free 0, system-wide uuid 0, minimum percentage of free blocks 5, TIME 
> optimization
> 
> This example is done on NetBSD/amd64 current.
> I believe "Unix Fast File system [v2]" means FFSv2.
Yes

The installboot(8) manual page
http://netbsd.gw.com/cgi-bin/man-cgi?installboot++NetBSD-current
also mentions in the examples that Pre NetBSD 6.0 systems amd/i386
defaulted to FFSv1 so it's imortant to make sure one is installing
the correct ones, for which dumpfs(8) can be used.

If you file a PR I can see that
http://www.netbsd.org/docs/guide/en/chap-rf.html#chap-rf-setup-filesystems
gets some additional warnings regarding the FFSv1/v2 transition
pre/post NetBSD 6.0 on amd/i386.

Adrian