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Date: Fri, 24 Apr 2009 10:22:56 +1000
From: Andrew Snow <andrew@modulus.org>
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Cc: freebsd-fs@freebsd.org
Subject: Re: UFS2 metadata checksums
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Ideally you would implement complete disk checksumming as a GEOM device.

Then you could layer geom_mirror on top of it, so that if the checksum 
fails and returns EIO, geom_mirror can try the alternate device and 
rebuild the one with the bad checksums.

That will then complete the feature set implemented by ZFS, but for any 
filesystem on top of GEOM.

- Andrew