lapsio@raid ~> sudo btrfs fi show /dmnt/raid/

This is : RAID
Label: 'raid'  uuid: 9f52965f-09de-4ab3-848c-2a053a55e96b
        Total devices 8 FS bytes used 8.59TiB
        devid    1 size 1.82TiB used 1.48TiB path /dev/sdb
        devid    2 size 1.82TiB used 1.48TiB path /dev/sdc
        devid    3 size 1.82TiB used 1.48TiB path /dev/sdd
        devid    4 size 1.82TiB used 1.48TiB path /dev/sde
        devid    5 size 1.82TiB used 1.48TiB path /dev/sdf
        devid    6 size 1.82TiB used 1.48TiB path /dev/sdg
        devid    7 size 1.82TiB used 1.48TiB path /dev/sdh
        devid    8 size 1.82TiB used 1.48TiB path /dev/sdi