Manually partitioning drives for 4K sector

[aufalien]

I almost shudder to ask this question.

However in FreeNAS 9.1.1 I used to manually partition drives as follows;

gpart create -s GPT da#

gpart add -t freebsd-zfs -b 128 -s #G da#

This was done to under provision drives for ZIL use.

In 9.2.1.3, when do the same procedure and add the drives to ZIL, zdb shows an ashift of 9.

I've tried different permutations;

gpart add -t freebsd-zfs -a 4k -b 1M da#
gpart add -t freebsd-zfs -b 2048 da#
gpart add -t freebsd-zfs -a 8 da#

... and combos there after, but zdb still shows an ashift of 9. When letting FreeNAS do it via the UI. ashift 12 shows.

All of my vdevs show 12 except for ZIL when manually partitioning it.

I'm only doing this on my ZIL drives. Any clues would be greatly appreciated.

Thanks in advance.

 

[aufalien]

Alrighty, I did the gnop approach were by you create a gnop device based on the partition and specifying -S 4096, use that to add a ZIL and in my case I rebooting knowing gnop device do not persist across reboots.

Or you can export the pool, remove the gnop and import it back again although I haven't tried this myself.

Was hoping to avoid the gnop method but it works well enough.