OBSOLETE CONTENTThis wiki has been archived and the content is no longer updated. Multiple devices A Btrfs filesystem can be created on top of many devices, and more devices can be added after the FS has been created. By default, metadata will be mirrored across two devices and data will be striped across all of the devices present. This is equivalent to mkfs.btrfs -m raid1 -d raid0. If only one d