From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: RAID5 - Disk failed during re-shape Date: Mon, 13 Aug 2012 09:35:54 +1000 Message-ID: <20120813093554.600d46c2@notabene.brown> References: <50258CEA.10100@turmel.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/rJrnSU4G8o4f94POI5WPBbl"; protocol="application/pgp-signature" Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Sam Clark Cc: Phil Turmel , "linux-raid@vger.kernel.org" List-Id: linux-raid.ids --Sig_/rJrnSU4G8o4f94POI5WPBbl Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Sat, 11 Aug 2012 10:42:01 +0200 Sam Clark wrote: > Thanks for the response Phil.=20 >=20 > I was thinking that 'toast' was the case, and have been looking into my b= ackups (not so great, though the critical data is fine).=20 >=20 If you've got backups, then that is likely the most reliable solution - sor= ry. > I think you are toast, as I saw nothing in the metadata that would give > you a precise reshape restart position, even if you got Neil to work up > a custom mdadm that could use it. The 11.4% could be converted into an > approximate restart position, perhaps. >=20 > Neil, is there any way to do some combination of "create > --assume-clean", start a reshape held at zero, then skip 11.4% ? The metadata might contain the precise reshape position - but "mdadm --examine" won't be displaying it. If you can grab the last 128K of the device (probably using 'dd' with 'skip=3Dxxx' I would be able to check and see. If you can tell me: exactly how big the devices are (sectors) what the chunk size of the array was (probably 64K) and get me that last 128K of a few devices, then I can provide you a shell script that will poke around in sysfs and activate the array in read-only mode which might allow you to mount it and copy out any important data. After that you would need to re-create the array. I don't think it is really practical to get the array fully working again with recreating from scratch once you have all the important data. NeilBrown --Sig_/rJrnSU4G8o4f94POI5WPBbl Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.18 (GNU/Linux) iQIVAwUBUCg92jnsnt1WYoG5AQLz0A/+Kp8YwKb/VmmEuyHoW5wv7GXJZ062sWOC msfxAvFRb3v8qqWBoaaMUGNVoDtFU8a0DQ8ucLE0whGyIGR6FpMcbnNyS5mqKnl0 CEdVODckPfYbLUtJ2pIwzbKC0dYtvn2/x0tjRbrjc5rrbpnNZaGqTtqbxilVHwVU 4wMaMe1r9z5cr4eg4OU6ZgVvLGFEGidYoFL/iJaqCt7aRyCxuhpzf/sjOVPfkeaI HlBW2byVeFTufa+stKGxFD3T5akTC6ZszR3mZ371Ilt/sOuGLIjSN5+AQ3fxG5Zr 7UpDAmRh4G+v2iEUESS2hYFgxpgA+DZnK1IZAcebo22THeBLc+YL9tknwIbnMtx/ Mq1aAqL8t+rIR9w3VCOP82z9JDSdPheVLvucY/avw5Dt/JgCeRYZWbgnkhKkb157 4dmUPODxHn0M27ijiQd3Xz80G/NsBSwWQfhkAcrST+BXUESjjTt6PkHbf4r99pmH djsRTHYHg4dOUDUHrBP3FoUX4HLnJzfUD3V5HaShAq2cnrTVekdggfw9QCbBowTE KJP56VY2HRrbGsayZKDzp9/TNA0NLY7ocdl3xwMM16bMnkt/H+rUhP4YaIONHrn0 LQdr8ioPDzjXnxTy+fsbEyyRIt4fIp2d7O7YVTI7zWRzydCNfucVpbFoCzxR0gmv Xe27m/QoKG0= =7BU8 -----END PGP SIGNATURE----- --Sig_/rJrnSU4G8o4f94POI5WPBbl--