Re: changes to the zfs boot (was: Re: git: 72a1cb05cd23 - main - rc(8): Add a zpoolupgrade rc.d script)

On Nov 9, 2022, at 12:56, Warner Losh <imp@bsdimp.com> wrote:

> On Wed, Nov 9, 2022 at 1:54 PM Patrick M. Hausen <pmh@hausen.com> wrote:
> 
> > Am 09.11.2022 um 21:51 schrieb Warner Losh <imp@bsdimp.com>:
> > Yes. For safety, boot loader upgrade is mandatory when you do a zpool upgrade of the root filesystem.
> > It was definitely needed in the OpenZFS jump, and we've had one or two other flag days since.
> 
> That's a given and not a problem. What I fear from my understanding of this thread so far is
> that there might be a situation when I upgrade the zpool and the boot loader and the system
> ends up unbootable nonetheless.
> 
> Possible or not?
> 
> If all you do is upgrade, then no, modulo bugs that we've thankfully not had yet.

I guess you mean FreeBSD upgrade, not zpool updgrade?

For zpool upgrade after a main [so: 14] FreeBSD upgrade . . .

As I understand it, com.delphix:head_errlog was not added to
the loader until after some folks had done a zpool upgrade
and then could not boot. The loader was updated in response
to the people's problem with trying to boot.

Of course, this was main, not stable or releng/13.* or the
like. There is more control over the staging of updates
for them.

It would be nice if UPDATING reported when a openzfs update
was adding new zpool feature(s) to main and if the loader
was ready for them yet. If not: Later adding an entry for
the loader being ready for the feature(s).

> It's when you enable something on the zpool that you can run into trouble, but that's true independent of upgrade :)
> 
> Warner
>   Modulo bugs, try test systems first, etc. Of course.
> 

===
Mark Millard
marklmi at yahoo.com