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Date: Tue, 05 Feb 2008 07:16:19 -0700
From: Joe Peterson <joe@skyrush.com>
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To: Nick Gustas <freebsd-stable@tychl.net>
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Cc: freebsd-fs@freebsd.org
Subject: Re: Forcing full file read in ZFS even when checksum
	error	encountered
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Nick Gustas wrote:
>> Well, I'd like to actually read the "bad" data too, so I can see if it is
>> really bad or if there is a metadata issue.  Basically, I'd like to recover
>> all the file's bytes this once without having ZFS stop me due to the checksum
>> failure, just for debugging purposes.  Is this impossible in ZFS?
> This may do what you want, but I'm not sure if this only disables 
> creation of checksums, or it disables use of preexisting checksums 
> entirely. The man page entry would suggest it disables them for reads 
> too. If this is the case, it should do what you want.
>
> http://www.solarisinternals.com/wiki/index.php/ZFS_Evil_Tuning_Guide#Checksums

Unfortunately, no - I tried this already, and it has no effect.  I assume it
only determines whether the checksums are created, not whether checked if they
already exist.

						Thanks, Joe