Another issue to consider.

At least for an Alpha DS10L, if its OPA0 is hardwired to a VAX TX port,
the booting process may halt somewhere once the buffers are full due to
an XOFF (or hardware equivalent) situation on the VAX's TX port.

(I just experienced this while I was away).

So you may wish to add /NOHOSYNC and /NOTTSYNC to the permanent
definition so that the hardware will not tell the alpha to stop sending
data.