From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: Help needed recovering from raid failure Date: Fri, 1 May 2015 12:31:14 +1000 Message-ID: <20150501123114.390234c8@notabene.brown> References: <20150430092741.0dc24c39@notabene.brown> <75230D05-6BFF-4906-921A-15175D6567EB@gmail.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/UkhBG+a3YduO+AAqI8rHA=Y"; protocol="application/pgp-signature" Return-path: In-Reply-To: <75230D05-6BFF-4906-921A-15175D6567EB@gmail.com> Sender: linux-raid-owner@vger.kernel.org To: Peter van Es Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids --Sig_/UkhBG+a3YduO+AAqI8rHA=Y Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Thu, 30 Apr 2015 21:25:04 +0200 Peter van Es wro= te: > Neil, >=20 > thanks. I followed your instructions (slightly modified as my version of = mdadm did not support the --data-offset stanza). /dev/sdd was the 3rd drive= and I had physically removed the 4th drive from my server. >=20 > I managed to restart the array. Then I replaced the failing drive, create= d partitions the same as on /dev/sda and added it to the two arrays. >=20 > It is now rebuilding for the data array, and will be done in 440 minutes.= ... It appears that I've lost nothing important... Excellent. >=20 > One question: I did spot that the Array UUID has changed on the Create co= mmand. Is there any way of getting it back to the old value ? Why would you want to? But I think you can. Firstly stop the array (so you need to be booted from= a USB or similar) and then mdadm --assemble /dev/mdWHATEVER --update=3Duuid --uuid=3Dyour:favo:rite:n= ums ..list.of.devices.. NeilBrown >=20 > Peter >=20 >=20 > >=20 > > Before doing this, double check that the names have changed, so check t= hat > > mdadm --examine /dev/sda2 > > shows > >> Array UUID : 1f28f7bb:7b3ecd41:ca0fa5d1:ccd008df > >> Device Role : Active device 0 > >=20 > > (among other info) and that=20 > > mdadm --exmaine /dev/sdb2 > > show the same Array UUID and > >> Device Role : Active device 1 > >=20 > >=20 > > Then run > >=20 > > mdadm -C /dev/md1 -l5 -n4 --data-offset=3D262144s --metadata=3D1.2 --as= sume-clean \ > > /dev/sda2 /dev/sdb2 missing /dev/sde2 >=20 --Sig_/UkhBG+a3YduO+AAqI8rHA=Y Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIVAwUBVULlcjnsnt1WYoG5AQIayg//b3mrnr9vdoWZXAOPkcd8HyGMJVLGKW/D XeDbiqRJbl4avh0JVOt29zDQKFT38ElAvxtEUutr5kvK6Oe2rD4CdiG6NkNs6Kg8 oDCAyRhOLok5b8nknjCy9m/ZBbwTvADsaCIOZ8rCTQ+3HcO1OAygaw01omZRdCnb ZrGilzulgaW3fpen4SxbJvlF/ESYwlAw8jfIghxb59lPsBYme8XoVfIxBtfYxZI9 qaNpUuToajCrlEvuDqONbxZqnP1XrPtgYLJWX5uV28NJrV7pSZ73JNWxKfzdk+Xw 2sY+jgJrkJ/kABTpzZNdPcGjC1QH/1mkk/AyiAiICkkX99DBeLExWvFc/ZOx9cUi PSaeKDzjiMx6iNGJBLIQwxfl5mSzdBewimXit28cAnYLSNjIixk07fQ03xkr1iz1 ijYV8emLGU6xfnDM74dPNCKpWSVxAKOPdTsY5qixa1visrplkuAWSmj3RI6Dp82l Y3dTKYOS1DbutnJ35vHNWIxCnnn2XnPo9PVFedTU23LGV79k6hqtqdmPazk93B4o 1UhPU1R/OzQ8NBRrBO8AHO3la6LiyZUqHi5lF/zWxlkjWwKnsHEkN3irtL/cLvHQ 4zgzqw8VOybbAnLekB9PhGGFdQwlVM4u6VAu6hpUEo9r5+siwz0Vvfs+eGEYO/fR DXr1UzMnL6s= =Q5K2 -----END PGP SIGNATURE----- --Sig_/UkhBG+a3YduO+AAqI8rHA=Y--