zpool component names - gpt vs. gptid

[Arthur Chance]

On 05/11/2014 09:27, Trond Endrestøl wrote:
> On Wed, 5 Nov 2014 09:06-0000, Arthur Chance wrote:
>
>> These days I use GPT labelled partitions (/dev/gpt/<label>) exclusively when
>> creating zfs pools. However, on my latest box, where I have two pools each
>> with a single component, "zpool status" lists the components as gptid/<uuid>
>> rather than gpt/<label>
>>
>> Is there any way to persuade zfs/zpool to use the GPT label devices rather
>> than the gptid devices? Failing that, how do you map gptid's back to the
>> underlying disk partitions? It's obvious in this case, but I'm building a new
>> file server with eight identical disks in a raidz2 set up and am worried how
>> I'll identify which disk has problems in the future.
>
> Look at: zpool import -d /dev/gpt some-zpool
>

I tried that before (after exporting the zpool of course) and it failed. 
Looking a bit harder, the /dev/gpt device had ceased to exist because 
the corresponding /dev/gptid device was active. Retasting the disk 
brought the gpt dive back, and importing with -d worked for one zpool. 
However, the other has root on it and I'd have to do it from a live 
memory stick.

However, none of this explains why zpool was using the gptid disks - I'd 
created the pools using gpt labelled disks and that got lost over some 
reboot, and I'd like to stop that happening again. The problem is that I 
don't know why it happened. I recently started using boot environments 
in order to switch from 10.1-RC3 to -RC4, but I'm not sure if that's 
connected - /boot and the zfs cache are within the b.e. and should have 
been copied over.