RL02 headache

[speck at brl-tgr.ARPA]

    Our brand-new (Rev. 7) 750's came with RL02's instead of tape drives
(bad idea!) so to bring up 4.2bsd I've put enough on the RL02 to be able
to copy the rest via Ethernet.	Partway through the copy I get hard RL02
errors (data late, operation incomplete); when I power-cycle and reboot,
fsck finds the same thing, same sector.  The DEC FE speculates that that
sector's header gets messed up.  VMS BAD and EVRAA give the pack a clean
bill of health; if I rewrite it, it's fine again until I try copying via
Ethernet onto the RA81.  Same on both vaxes, I tried pack swaps, etc.

    The RL211 controller is at the head of the Unibus, followed by the
DZ-11 (unused so far), an Interlan 10 Mbit Ether card, and the UDA-50.
During the copy the latter two boards must be really hogging the bus -
is that what the `data late' error-bit is about?  DEC blames it on the
software 'cause it does the same thing on both machines.  Anybody have
any clues/fixes/suggestions?
				Don Speck	speck at cit-vax.arpa
				I get unix-wizards but not info-vax.