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Date: Sun, 27 Feb 2011 13:57:14 -0600
From: "James R. Van Artsdalen" <james-freebsd-fs2@jrv.org>
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To: Emil Smolenski <am@raisa.eu.org>
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Cc: freebsd-fs@freebsd.org
Subject: Re: [ZFS] Booting from zpool created on 4k-sector drive
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Emil Smolenski wrote:
> Hello,
>
> There is a hack to force zpool creation with minimum sector size equal
> to 4k:
>
> # gnop create -S 4096 ${DEV0}
> # zpool create tank ${DEV0}.nop
> # zpool export tank
> # gnop destroy ${DEV0}.nop
> # zpool import tank
>
> This change is permanent. The only possibility to change the value of
> ashift is: zpool destroy/create and restoring pool from backup.

Is ashift a property of the pool or a property of the device?

I'm wonder about the disk replacement scenario, where the replacement
disk cannot be smaller than the disk it replaces.