Well, excuse me for thinking it wouldn't since in md-raid it worked. https://wiki.archlinux.org/index.php/RAID#RAID_level_comparison
Anyway, the error message is truly confusing for someone who doesn't know about btrfs's implementation. I suppose in md-raid the near layout is actually RAID 1 and far2 uses twice as much space. https://en.wikipedia.org/wiki/Non-standard_RAID_levels#LINUX-MD-RAID-10 Well, I guess I'll go with RAID 1, then. Thanks for clearing up the confusion. ke 28. marrask. 2018 klo 3.14 Qu Wenruo (quwenruo.bt...@gmx.com) kirjoitti: > > > > On 2018/11/28 上午5:16, Mikko Merikivi wrote: > > I seem unable to convert an existing btrfs device array to RAID 10. > > Since it's pretty much RAID 0 and 1 combined, and 5 and 6 are > > unstable, it's what I would like to use. > > > > After I did tried this with 4.19.2-arch1-1-ARCH and btrfs-progs v4.19, > > I updated my system and tried btrfs balance again with this system > > information: > > [mikko@localhost lvdata]$ uname -a > > Linux localhost 4.19.4-arch1-1-ARCH #1 SMP PREEMPT Fri Nov 23 09:06:58 > > UTC 2018 x86_64 GNU/Linux > > [mikko@localhost lvdata]$ btrfs --version > > btrfs-progs v4.19 > > [mikko@localhost lvdata]$ sudo btrfs fi show > > Label: 'main1' uuid: c7cbb9c3-8c55-45f1-b03c-48992efe2f11 > > Total devices 1 FS bytes used 2.90TiB > > devid 1 size 3.64TiB used 2.91TiB path /dev/mapper/main > > > > Label: 'red' uuid: f3c781a8-0f3e-4019-acbf-0b783cf566d0 > > Total devices 2 FS bytes used 640.00KiB > > devid 1 size 931.51GiB used 2.03GiB path /dev/mapper/red1 > > devid 2 size 931.51GiB used 2.03GiB path /dev/mapper/red2 > > RAID10 needs at least 4 devices. > > Thanks, > Qu > > > [mikko@localhost lvdata]$ btrfs fi df /mnt/red/ > > Data, RAID1: total=1.00GiB, used=512.00KiB > > System, RAID1: total=32.00MiB, used=16.00KiB > > Metadata, RAID1: total=1.00GiB, used=112.00KiB > > GlobalReserve, single: total=16.00MiB, used=0.00B > > > > --- > > > > Here are the steps I originally used: > > > > [mikko@localhost lvdata]$ sudo cryptsetup luksFormat -s 512 > > --use-random /dev/sdc > > [mikko@localhost lvdata]$ sudo cryptsetup luksFormat -s 512 > > --use-random /dev/sdd > > [mikko@localhost lvdata]$ sudo cryptsetup luksOpen /dev/sdc red1 > > [mikko@localhost lvdata]$ sudo cryptsetup luksOpen /dev/sdd red2 > > [mikko@localhost lvdata]$ sudo mkfs.btrfs -L red /dev/mapper/red1 > > btrfs-progs v4.19 > > See http://btrfs.wiki.kernel.org for more information. > > > > Label: red > > UUID: f3c781a8-0f3e-4019-acbf-0b783cf566d0 > > Node size: 16384 > > Sector size: 4096 > > Filesystem size: 931.51GiB > > Block group profiles: > > Data: single 8.00MiB > > Metadata: DUP 1.00GiB > > System: DUP 8.00MiB > > SSD detected: no > > Incompat features: extref, skinny-metadata > > Number of devices: 1 > > Devices: > > ID SIZE PATH > > 1 931.51GiB /dev/mapper/red1 > > > > [mikko@localhost lvdata]$ sudo mount -t btrfs -o > > defaults,noatime,nodiratime,autodefrag,compress=lzo /dev/mapper/red1 > > /mnt/red > > [mikko@localhost lvdata]$ sudo btrfs device add /dev/mapper/red2 /mnt/red > > [mikko@localhost lvdata]$ sudo btrfs balance start -dconvert=raid10 > > -mconvert=raid10 /mnt/red > > ERROR: error during balancing '/mnt/red': Invalid argument > > There may be more info in syslog - try dmesg | tail > > code 1 > > > > [mikko@localhost lvdata]$ dmesg | tail > > [12026.263243] BTRFS info (device dm-1): disk space caching is enabled > > [12026.263244] BTRFS info (device dm-1): has skinny extents > > [12026.263245] BTRFS info (device dm-1): flagging fs with big metadata > > feature > > [12026.275153] BTRFS info (device dm-1): checking UUID tree > > [12195.431766] BTRFS info (device dm-1): enabling auto defrag > > [12195.431769] BTRFS info (device dm-1): use lzo compression, level 0 > > [12195.431770] BTRFS info (device dm-1): disk space caching is enabled > > [12195.431771] BTRFS info (device dm-1): has skinny extents > > [12205.815941] BTRFS info (device dm-1): disk added /dev/mapper/red2 > > [12744.788747] BTRFS error (device dm-1): balance: invalid convert > > data profile raid10 > > > > Converting to RAID 1 did work but what can I do to make it RAID 10? > > With the up-to-date system it still says "invalid convert data profile > > raid10". > > >
