Re: Building ZFS disk images

From: Rodney W. Grimes <freebsd-rwg_at_gndrsh.dnsmgr.net>
Date: Tue, 28 Sep 2021 15:48:35 UTC
> On Mon, Sep 27, 2021 at 1:54 PM Mark Johnston <markj@freebsd.org> wrote:
> >
> > On Thu, Aug 05, 2021 at 10:54:19AM -0500, Alan Somers wrote:
> > > There's this:
> > > https://openzfs.github.io/openzfs-docs/man/8/zpool-reguid.8.html .  I
> > > haven't used it myself.
> >
> > Would it be useful to have an rc.d script that can run this, probably
> > just on the root pool?  It could be configured to run only upon the
> > first boot, like growfs already does.
> 
> Absolutely!

Ewwwwwwwwww!  :-)

> >
> > > On Thu, Aug 5, 2021, 9:29 AM David Chisnall <theraven@freebsd.org> wrote:
> > >
> > > > On 05/08/2021 13:53, Alan Somers wrote:
> > > > > I don't know of any way to do it using the official release scripts
> > > > > either. One problem is that every ZFS pool and file system is supposed
> > > > > to have a unique GUID.  So any kind of ZFS release builder would need to
                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
> > > > > re-guid the pool on first boot.

Isnt the proper place to solve this lack of Unique UUID creation
in the tool(s) that are creating the zfs pool in the first place.

Fixing it "post boot" seems to be a far to late hack and doesnt
fix any of the situations where one might import these pools
between creation and first boot.

> > > >
> > > > Is there a tool / command to do this?  I've hit this problem in the
> > > > past: I have multiple FreeBSD VMs that are all created from the same
> > > > template and if one dies I can't import its zpool into another because
> > > > they have the same UUID.
> > > >
> > > > It doesn't matter for modern deployments where the VM is stateless and
> > > > reimaged periodically but it's annoying for classic deployments where I
> > > > have things I care about on the VM.
> > > >
> > > > David
> 
> 

-- 
Rod Grimes                                                 rgrimes@freebsd.org