Matthew Dillon dillon at
Tue Jul 7 17:47:37 PDT 2009

:Running this *online* couldn't find any 'B', so I guess I have to
:boot it with a USB memory stick and try it again?
:I'll also try memtest after that.  Thanks for the hint.

    It's possible that HAMMER caught the problem before it wrote the
    sector back to disk, in which case it may only have gotten corrupted
    in-memory and the filesystem on-media might be ok.

    You can validate the entire filesystem offline (or if it is completely
    idle) with:

	hammer -f <device> show | egrep '^B'
	(that's carrot and B, not control-B)

    If no lines are marked bad in the show output then the filesystem is
    clean.  This can take a while to run since it reads every single last
    bit of meta-data and data in the filesystem.  If any hammer cleanup
    or reblocking op runs while the show is running the show command
    will blow up.

    The most likely scenario is that there's bad ram.

					Matthew Dillon 
					<dillon at>

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