From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phil Turmel Subject: Re: RAID6 recovery with 6/9 drives out-of-sync Date: Wed, 1 Jun 2016 08:06:58 -0400 Message-ID: <574ECFE2.9050602@turmel.org> References: <574DE3B0.8000409@turmel.org> <5D9C8773-D76E-409F-8961-41EB3ACD177A@illinois.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <5D9C8773-D76E-409F-8961-41EB3ACD177A@illinois.edu> Sender: linux-raid-owner@vger.kernel.org To: "Peckins, Steven E" Cc: "linux-raid@vger.kernel.org" List-Id: linux-raid.ids On 06/01/2016 07:32 AM, Peckins, Steven E wrote: >=20 > On May 31, 2016, at 2:19 PM, Phil Turmel wrote: >=20 >> On 05/30/2016 10:43 PM, Peckins, Steven E wrote: >>> >>> The component devices in the array are supposed to be multipath dev= ices (dm-multipath), but for some reason, when the server was restarted= , md grabbed both dm-* components and raw devices. I *think* that this= is what caused the problem. >> >> Quite possible. You probably need a DEVICES clause in your mdadm.co= nf >> to exclude the raw devices from the arrays. >=20 > I had a typo in the DEVICE glob for the system disks (/dev/sd[ab]* in= stead of /dev/sd[ab][12]). Understood, but be aware that if you have to hotswap one of these syste= m devices, they may not get the sda or sdb name, preventing a re-add or a replacement from joining the array. Since you are having to use /dev/mapper entries for some arrays, consider using /dev/disk/by*/ symlinks for your system arrays. >>> I'm seeking advice on how to proceed at this point. If more inform= ation is required, please ask. >> >> Hmmm. The partial success on mdadm --force suggests trying that aga= in. >> Possible with --force twice on the command line. >> >> Forced assembly is precisely what you need -- don't despair and atte= mpt >> anything else. >=20 > Repeating the command was not successful; it is still reporting "/dev= /md10 assembled from 5 drives and 1 spare - not enough to start the arr= ay." Four drives are listed as =E2=80=9Cpossibly out of date." I assu= me those are the four that are not being incorporated. >=20 > Output from --assemble --force 1x and 2x: http://pastebin.com/k1dT2z= YC { In the future, please paste these in-line so the archives will have them. The size limit for this list is ~ 100k. } I vaguely recall a bug in forced reassembly for many out-of-date drives= =2E Please clone and build the latest mdadm userspace[1] and run that mdad= m binary for the forced assembly. Also show the portion of dmesg that corresponds to the attempt. Phil [1] https://github.com/neilbrown/mdadm -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html