From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hullen@t-online.de (Helmut Hullen) Subject: Re: failed disk Date: 09 May 2012 17:14:00 +0200 Message-ID: References: <20120509143735.GQ8938@carfax.org.uk> Reply-To: helmut@hullen.de Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII To: linux-btrfs@vger.kernel.org Return-path: In-Reply-To: <20120509143735.GQ8938@carfax.org.uk> List-ID: Hallo, Hugo, Du meintest am 09.05.12: >>> mkfs.btrfs -m raid1 -d single should give you that. >> Just a small bug, perhaps: >> >> created a system with >> >> mkfs.btrfs -m raid1 -d single /dev/sdl1 >> mount /dev/sdl1 /mnt/Scsi >> btrfs device add /dev/sdk1 /mnt/Scsi >> btrfs device add /dev/sdm1 /mnt/Scsi >> (filling with data) >> >> and >> >> btrfs fi df /mnt/Scsi >> >> now tells >> >> Data, RAID0: total=183.18GB, used=76.60GB >> Data: total=80.01GB, used=79.83GB >> System, DUP: total=8.00MB, used=32.00KB >> System: total=4.00MB, used=0.00 >> Metadata, DUP: total=1.00GB, used=192.74MB >> Metadata: total=8.00MB, used=0.00 >> >> -------------------------------------- >> >> "Data, RAID0" confuses me (not very much ...), and the system for >> metadata (RAID1) is not told. > DUP is two copies of each block, but it allows the two copies to > live on the same device. It's done this because you started with a > single device, and you can't do RAID-1 on one device. The first bit > of metadata you write to it should automatically upgrade the DUP > chunk to RAID-1. Ok. Sounds familiar - have you explained that to me many months ago? > As to the spurious "upgrade" of single to RAID-0, I thought Ilya > had stopped it doing that. What kernel version are you running? 3.2.9, self made. I could test the message with 3.3.4, but not today (if it's only an interpretation of always the same data). > Out of interest, why did you do the device adds separately, > instead of just this? a) making the first 2 devices: I have tested both versions (one line with 2 devices or 2 lines with 1 device); no big difference. But I had tested the option "-L" (labelling) too, and that makes shit for the oneliner: both devices get the same label, and then "findfs" finds none of them. The really safe way would be: deleting this option for the "mkfs.btrfs" command and only using btrfs fi label [] b) third device: that's my usual test: make a cluster of 2 deivces fill them with data add a third device delete the smallest device Viele Gruesse! Helmut