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Subject: Re: ZFS: Is 'zpool add' really irreversible?
To: "Brandon J. Wandersee" <brandon.wandersee@gmail.com>
References: <d13abf72-3903-796a-1d47-e3a7b776ebf8@rawbw.com>
 <86shwiax38.fsf@WorkBox.Home>
Cc: FreeBSD Questions <freebsd-questions@freebsd.org>
From: Yuri <yuri@rawbw.com>
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Date: Sun, 12 Jun 2016 15:14:12 -0700
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On 06/12/2016 14:58, Brandon J. Wandersee wrote:
> `zpool add` adds*virtual*  devices to a*pool*, while `zfs attach` adds
> physical devices to a mirrored device. So individual disks can be added
> to and removed from mirrored virtual devices, but virtual devices cannot
> be removed from a pool.


Thank you for your answer. I see that ZFS is designed this way.

But I can't say I like this part of ZFS design. Because this isn't a 
physical disk with the set size, but a combination of disks. People may 
reasonably want to remove some disks in some layouts, due to failures, 
etc, and ZFS just lacks the flexibility to do that.


Thanks!

Yuri