> 
[...]

> ra0 at uda0 slave 0: attempt to bring on line failed:  media format
> 	error (unknown subcode) (code 5, subcode 6)
> : offline
>         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>         what does subcode 6 mean???
> 
The problem is that your RQDX controller cannot bring your RD54
online (an internally state of the controller). This usually means
that a controller-specific ID on the disk has been destroyed, and
the disk needs to be re-formatted.

About the subcode: There are no explanation on DEC docs what it
means. This is what a comment in mscp.c says about this:

/*
 * The code is the lower six bits of the event number (aka
 * status).  If that is 6 (write protect), the subcode is in
 * bits 12-15; otherwise, it is in bits 5-11.
 * I WONDER WHAT THE OTHER BITS ARE FOR.  IT SURE WOULD BE
 * NICE IF DEC SOLD DOCUMENTATION FOR THEIR OWN CONTROLLERS.
 */

-- Ragge