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Subject: Re: Can't use gpt labels re-importing pool
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Jeremy Chadwick wrote:

> Why are people bothering with GPT labels (or in some cases, glabels)
> when AHCI (whether it be ataahci.ko or ahci.ko) is in use?  Under what
> circumstance would the device name change dynamically in this situation?
> 
> I've never witnessed this happening with AHCI, at least on Intel
> systems, and I've hot-swapped hard disks many times over.

It isn't specific to AHCI, but this is where most people encountered it 
first. The issue in question is "how to make ZFS survive drive renaming" 
for any cause - driver change, controller change, drive shuffling, etc.

In general, ZFS will taste individual drives on "zpool import" so will 
try to do the right thing, but it might pick up different labels for 
different drives, etc. Using glabel tricks simply makes the naming a bit 
more consistent.