[OpenIndiana-discuss] ways to move from sliced rpool to gpt/EFI rpool

[Harry Putnam]

Nikola M <minikola at gmail.com> writes:

> On 03/22/17 02:21 PM, Carsten Grzemba wrote:
>> Is there a way to migrate a sliced (mirrored) rpool on disks with
>> msdos partition table to gpt partioned disks (EFI lable)
>> with loader?
>
> Yes, you fully reformat one drive and do fresh install on it, then
> vtoc + zpool attach other drives to it.
> https://wiki.openindiana.org/oi/2.1+Post-installation
> (Or with newest Openindiana hipster snapshot media, installer can take
> multiple devices and install on them during install.)
> GPT and MBR disk partition types are mutually exclusive.

Although other aspects are fully covered, the cited URL does not
appear to explain what is meant by `fully reformat'.

Can you explain what that means?