zpool upgrade instructions aren't complete enough - gpart operation not permitted

[Paul Hargreaves]

Hi there,

Just upgraded from 10.2 to 11.0.
As part of that, did zpool upgrade:

root at zfsbackup:~ # zpool upgrade zroot
This system supports ZFS pool feature flags.

Enabled the following features on 'zroot':
  sha512
  skein

If you boot from pool 'zroot', don't forget to update boot code.
Assuming you use GPT partitioning and da0 is your boot disk
the following command will do it:

	gpart bootcode -b /boot/pmbr -p /boot/gptzfsboot -i 1 da0


Ok, I think I’m using GPT partitioning and I think I boot from da0 (specifically, zpool show shows zroot is da0s1d), but how to tell?

root at zfsbackup:~ # gpart bootcode -b /boot/pmbr -p /boot/gptzfsboot -i 1 da0
gpart: /dev/da0s1: Operation not permitted

Hmm…  ok.

Google-fu only found this: https://wiki.freebsd.org/RootOnZFS/GPTZFSBoot
which doesn’t help since it’s out of date.

Is there a different magic incantation I should be using?

Also tried using the da0s1d but then get part: No such geom: da0s1d.

Regards

Paul