From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Hill Subject: Re: BUG:write data to degrade raid5 Date: Fri, 19 Mar 2010 18:30:31 +0000 Message-ID: <20100319183031.GA799@cthulhu.home.robinhill.me.uk> References: <4BA3C07A.8030204@gmx.net> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="bp/iNruPH9dso1Pn" Return-path: Content-Disposition: inline In-Reply-To: <4BA3C07A.8030204@gmx.net> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids --bp/iNruPH9dso1Pn Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri Mar 19, 2010 at 07:20:42PM +0100, Joachim Otahal wrote: > jin zhencheng schrieb: > > hi; > > > > i use kernel is 2.6.26.2 > > > > what i do as follow: > > > > 1, I create a raid5: > > mdadm -C /dev/md5 -l 5 -n 4 /dev/sda /dev/sdb /dev/sdc /dev/sdd > > --metadata=3D1.0 --assume-clean > > > > 2, dd if=3D/dev/zero of=3D/dev/md5 bs=3D1M& > > > > write data to this raid5 > > > > 3, mdadm --manage /dev/md5 -f /dev/sda > > > > 4 mdadm --manage /dev/md5 -f /dev/sdb > > > > if i faild 2 disks ,then the OS kernel display OOP error and kernel down > > > > do somebody know why ? > > > > Is MD/RAID5 bug ? > > =20 >=20 > RAID5 can only tolerate ONE drive to fail of ALL members. If you want to= =20 > be able to fail two drives you will have to use RAID6 or RAID5 with one= =20 > hot-spare (and give it time to rebuild before failing the second drive). > PLEASE read the documentation on raid levels, like on wikipedia. >=20 Yes, but the kernel should _not_ OOPS if two drives fail. However, given that the kernel version used is 18 months old, I'm not sure the bug report is particularly useful. If it's a distro-specific kernel then report the issue to them, otherwise try installing a more recent kernel release. Cheers, Robin --=20 ___ =20 ( ' } | Robin Hill | / / ) | Little Jim says .... | // !! | "He fallen in de water !!" | --bp/iNruPH9dso1Pn Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.14 (GNU/Linux) iEYEARECAAYFAkujwscACgkQShxCyD40xBL/2ACgri4AvJ1Ag+OLAn2c5S9JhBJS WZ0An1jaOnEKbRf7s7RXg1FlAR27DXFu =v75+ -----END PGP SIGNATURE----- --bp/iNruPH9dso1Pn--