Unlike master where the "--index" mkfs.lustre option is optional, Orion requires an index to be specified when formatting a target. Although Orion has already implemented this change, the manual page and usage information of mkfs.lustre have not been updated.

Another improvement that could be done here is that "--index 0" should be optional when formatting an MDT, since single-MDT configuration is likely to coexist with those that use DNE.