svn commit: r325860 - head/sbin/newfs

[Rodney W. Grimes]

[ Charset UTF-8 unsupported, converting... ]
> On Nov 15, 2017 1:51 PM, "Rodney W. Grimes" <freebsd at pdx.rh.cn85.dnsmgr.net>
> wrote:
> 
> [ Charset UTF-8 unsupported, converting... ]
> > On Nov 15, 2017 11:47 AM, "Rodney W. Grimes" <freebsd at pdx.rh.cn85.dnsmgr.
> net>
> > wrote:
> >
> > > Author: emaste
> > > Date: Wed Nov 15 18:40:40 2017
> > > New Revision: 325860
> > > URL: https://svnweb.freebsd.org/changeset/base/325860
> > >
> > > Log:
> > >   newfs: warn if newer than kernel
> > >
> > >   Creating a UFS filesystem with a newfs newer than the running kernel,
> > >   and then mounting that filesystem, can lead to interesting failures.
> > >
> > >   Add a safety belt to explicitly warn when newfs is newer than the
> > >   running kernel.
> >
> > You should probably make the warning if (newer || older) as
> > either is likely to have interesting side effects, as are
> > mounting ufs file systems on different versions.
> >
> >
> > Not really. The cg stuff is really only a hassle for the case ed is
> testing
> > for.
> 
> Its too late now, but if you take a newer ufs with the cg
> stuff in them and mount it on an old system it politly well
> corrupt the data that the newer kernel needs.  So your right,
> doing this check in newfs wont do anything, but I can tell
> you this tiny little chain has been a PITA for people that
> move HD around....
> 
> 
> Fsck automatically fixes issues like that. It recomputes the checksums.

Yes, but you do not know that this is needed until AFTER
you have mounted the "Clean" file system and started using it,
and then you get some nasty messages (though they are a little
better now than the original ones).  So then you have to
manually fire off a fsck on the volume...

> 
> > *Sigh*  why did not UFS grow a version number of its own
> > when things started to change other than UFS1 vs UFS2.
> >
> >
> > This isn't anything like those changes..
> 
> UFS changed in a way that makes it difficult to move
> UFS drives accross systems that are at differing versions.
> That IS bad no mater how you slice it.  I now have to make
> sure I fsck a drive when moving it from an old to new
> system to get the cg checksum stuff fixed.
> 
> 
> Except it isn't as bad as you say.

It is a distracting PITA, you probably dont move a
UFS formatted flash drive around between as many
differing systems as I do.


Oh, and can you please get a mail client that does
proper quoting?

> Rod Grimes
> rgrimes at freebsd.org

-- 
Rod Grimes                                                 rgrimes at freebsd.org