linux-kernel - Re: modifying degraded raid 1 then re-adding other members is bad

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 9 Aug 2006 08:33:24 +1000
From:	Neil Brown <neilb@...e.de>
To:	Krzysztof Halasa <khc@...waw.pl>
Cc:	Michael Tokarev <mjt@....msk.ru>,
	Alexandre Oliva <aoliva@...hat.com>,
	linux-raid <linux-raid@...r.kernel.org>,
	linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: modifying degraded raid 1 then re-adding other members is bad

On Tuesday August 8, khc@...waw.pl wrote:
> Michael Tokarev <mjt@....msk.ru> writes:
> 
> > Why we're updating it BACKWARD in the first place?
> 
> Another scenario: 1 disk (of 2) is removed, another is added, RAID-1
> is rebuilt, then the disk added last is removed and replaced by
> the disk which was removed first. Would it trigger this problem?
> 

No.  The removing and the adding will all move the event count clearly
forward and the removed drive will have an old event count and so will
not be considered for easy inclusion.


> > Also, why, when we adding something to the array, the event counter is
> > checked -- should it resync regardless?
> 
> I think it's a full start, not a hot add. For hot add contents of
> the new disk should be ignored.

See my other post for why I want to sometimes not do a recovery on a
hot-add.

NeilBrown
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/