+Force a particular format for the backing fs (ldiskfs, zfs).
+.br
+.IR zpool_specification " = [[<" vdev_type ">] <" device "> [<" device "> ...] [<" vdev_type ">] ...]"
+.br
+.IR vdev_type " ="
+.RB { mirror , raidz , raidz2 , raidz3 , cache }
+.br
+.IR device " = { " "Linux block device" " }"
+
+If no vdev_type is given, then the devices are used in a round-robin
+(striped) manner. See
+.BR zpool (8)
+for more details.