From mboxrd@z Thu Jan 1 00:00:00 1970 From: cwillu Subject: Re: Btrfs raid1 "full sized"? Date: Sun, 1 May 2011 14:02:23 -0600 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: linux-btrfs@vger.kernel.org To: =?UTF-8?Q?Claes_Gyllensw=C3=A4rd?= Return-path: In-Reply-To: List-ID: On Sun, May 1, 2011 at 12:33 PM, Claes Gyllensw=C3=A4rd wrote: > I've tried setting up a raid1 on two drives like this: > > mkfs.btrfs -m raid1 -d raid1 /dev/sdb /dev/sdc > > Then I copy my old install onto the new drives, and check the drives'= status: > > # mount | grep "on / " > /dev/sdb on / type btrfs (rw,noatime) > # btrfs fi df / > Data, RAID1: total=3D259.00GB, used=3D256.64GB > Data: total=3D8.00MB, used=3D0.00 > System, RAID1: total=3D8.00MB, used=3D44.00KB > System: total=3D4.00MB, used=3D0.00 > Metadata, RAID1: total=3D4.50GB, used=3D1.27GB > Metadata: total=3D8.00MB, used=3D0.00 > # btrfs fi show > Label: none =C2=A0uuid: c6c89292-ea29-484c-ad29-9003a5fedf90 > =C2=A0 =C2=A0 =C2=A0 =C2=A0Total devices 2 FS bytes used 257.93GB > =C2=A0 =C2=A0 =C2=A0 =C2=A0devid =C2=A0 =C2=A01 size 931.51GB used 26= 3.53GB path /dev/sdb > =C2=A0 =C2=A0 =C2=A0 =C2=A0devid =C2=A0 =C2=A02 size 931.51GB used 26= 3.51GB path /dev/sdc > > Label: none =C2=A0uuid: 6f2f8317-3012-4e79-a82d-ab2e8eaa6cd6 > =C2=A0 =C2=A0 =C2=A0 =C2=A0Total devices 1 FS bytes used 354.99GB > =C2=A0 =C2=A0 =C2=A0 =C2=A0devid =C2=A0 =C2=A01 size 465.65GB used 46= 5.65GB path /dev/sda2 > > My interpretation of the above data is that /dev/sdb and /dev/sdc are > exact mirrors of each other, and contain my / root partition. > > This would make complete sense if it wasn't for the fact that I've > copied all the data from /dev/sda2 onto /dev/sdb. From the informatio= n > above, it looks like the data has been split like in raid-0, instead > of the what I expect, mirrored like in raid-1. > > I tried reading the FAQ about "Why are there so many ways to check th= e > amount of free space?" hoping this would make it more clear, but it > doesn't. Can anyone tell me what's going on? > > I found one thread with a similar question that went unanswered, and > it was also back in 2008 so the answer might differ quite a bit > anyway. How did you copy it exactly? I see 100gb missing, which makes me wonder if you maybe had subvolumes on sdb, and used the -x option to rsync or similar: subvolumes count as different mounts for the purposes of --one-file-system'like options. Can you provide the df -h output for both filesystems, as well as the btrfs fi df for /dev/sda2? The total reported by du -sh for each would be useful as well as a sani= ty check. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" = in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html