btrfs raid10 mount fails

#uname -r
4.4.1

#btrfs --version
btrfs-progs v4.4

# mount -t btrfs -o ro,recovery /dev/xvdg /media/Files
mount: wrong fs type, bad option, bad superblock on /dev/xvdg,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so


# dmesg | tail
[  180.256220] BTRFS info (device xvdg): enabling auto recovery
[  180.256227] BTRFS info (device xvdg): disk space caching is enabled
[  180.258068] BTRFS: failed to read the system array on xvdg
[  180.276159] BTRFS: open_ctree failed


# btrfs fi show
Label: 'Files'  uuid: 0bdc22d7-7684-4a92-8589-45742101f04b
	Total devices 8 FS bytes used 2.87TiB
	devid    1 size 931.51GiB used 817.27GiB path /dev/xvdg
	devid    2 size 931.51GiB used 817.27GiB path /dev/xvdh
	devid    3 size 931.51GiB used 817.27GiB path /dev/xvdi
	devid    4 size 931.51GiB used 817.27GiB path /dev/xvdk
	devid    5 size 931.51GiB used 817.27GiB path /dev/xvdc
	devid    6 size 931.51GiB used 817.27GiB path /dev/xvdj
	devid    7 size 931.51GiB used 817.27GiB path /dev/xvdb
	devid    8 size 931.51GiB used 817.27GiB path /dev/xvde