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Date: Mon, 18 Oct 2010 12:03:20 +0100
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To: fjwcash@gmail.com, pjd@FreeBSD.org
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From: Pete French <petefrench@ticketswitch.com>
Cc: freebsd-fs@freebsd.org
Subject: Re: Converting a non-HAST ZFS pool to a HAST pool
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> HAST metadata takes much more space than glabel metadata. The latter
> takes only one sector, while the former depends on provider size, but we
> have to keep entire extent bitmap there, so definitely more than one
> sector.

I am attempting to do the same thing - convert a ZFS pool over to using
hast. I have a current setup using gmirror, ggated and a pair of labeled
drives. Luckily it seems that the meta data used by gmirror+glabel is biiger
than that used by hast - so I should be able to do this without recreating
the pool.

I only mention it here because I know that the gmirror+ggate is a fairly
common setup. If you start with labeled drives then you will be able to
migrate to hast without any downtime.

-pete.