can't mount RAID-1 btrfs after reboot

I can't mount RAID-1 btrfs after reboot (well, sort of).

Using 2.6.31-rc5 and btrfs-progs 0.19, I created a RAID-1 fileystem using these command line options:

# mkfs.btrfs -L btrfs-data -m raid1 -d raid1 /dev/sda4 /dev/sdb4

After which I was able to mount the filesystem with either of the below (or both):

# mount /dev/sda4 /mnt/btrfs-sda4

# mount /dev/sdb4 /mnt/btrfs-sdb4

After a reboot, I'm no longer able to mount the filesystem from /dev/sda4:

# mount /dev/sda4 /mnt/btrfs/

Mount command complains and doesn't mount it and says I can find more info in dmesg:

Btrfs loaded
device label btrfs-data devid 1 transid 67 /dev/sda4
btrfs: failed to read the system array on sda4
btrfs: open_ctree failed

I'm able to mount the filesystem by using /dev/sdb4:

# mount /dev/sdb4 /mnt/btrfs/

After which I can unmount it, and use /dev/sda4 to mount the filesystem:

# umount /dev/sdb4
# mount /dev/sda4 /mnt/btrfs/

Quoted 8 lines

I'm able to mount the filesystem by using /dev/sdb4:

# mount /dev/sdb4 /mnt/btrfs/

After which I can unmount it, and use /dev/sda4 to mount the filesystem:

# umount /dev/sdb4
# mount /dev/sda4 /mnt/btrfs/

Try btrfsctl -a first.

Quoted 9 lines · Jens Axboe

Quoted 8 lines

I'm able to mount the filesystem by using /dev/sdb4:

# mount /dev/sdb4 /mnt/btrfs/

After which I can unmount it, and use /dev/sda4 to mount the filesystem:

# umount /dev/sdb4
# mount /dev/sda4 /mnt/btrfs/

Quoted 1 line

Try btrfsctl -a first.

It seems to do the trick.

I suppose longer term, doing "btrfsctl -a" before mounting a (RAID) btrfs filesystem shouldn't be needed, or?