Subject: Re: 3ware's tw_cli management tool for twa(4) now runs on NetBSD
To: Emmanuel Dreyfus <>
From: Brian Buhrow <>
List: current-users
Date: 09/25/2006 08:47:19
	The rewriting of bad blocks on IDE disks in the 3ware firmware must
have been an additional feature which wasn't present in the cards I used
because it definitely wasn't working when I was using such cards.  When
disks had bad blocks on them, the card would simply label them as failed
disks.  Worse, when trying to rebuild such arrays, the disks would stil
fail, even though it should have been writing over the bad blocks.
	If the feature is there, it should work in raid mode or in jbod mode,
I should think.  If not, you can work around it in jbod mode, I believe, by
writing to the logically inaccessible block and then using raidframe to
rebuild your array.
On Sep 24, 11:17pm, Emmanuel Dreyfus wrote:
} Subject: Re: 3ware's tw_cli management tool for twa(4) now runs on NetBSD
} Manuel Bouyer <> wrote:
} > The adapter's firmware should be able to do automatic rewrite of
} > bad blocks. This is important especially for IDE drives, for which a
} > rewrite is required in order to remap the block (there's no automatic
} > remapping on too much read retries, as it can be configured on
} > SCSI disks). 
} But it still does that if the disk is exported as a single unit used by
} RAIDframe, doesn't it?
} > Also, for raid-5 the battery-backed cache of the
} > adapter helps a lot (if you didn't order the battery this won't
} > help of course :)
} Well, I don't have it. :-/
} -- 
} Emmanuel Dreyfus
>-- End of excerpt from Emmanuel Dreyfus