This might not be specific for pmax or NetBSD but I did the
following for many years on many platforms and now it gives
trouble on NetBSD 1.4.2 on pmax (3MIN with a few Storage
Expansion boxes):

Moved /usr from /dev/rz0d to /dev/rz3c in single user mode
with dump|restore, changing fstab accordingly and reboot.

Symptoms:
- Xserver dies with "Memory fault"
- syslogd dies with "syslogd: bind: Can't assign requested address"
   (so no errormessages in /var/log !!!)
- can not telnet to it: Escape character is '^]'.
                         Connection closed by foreign host.
- can not rsh to it: select: protocol failure in circuit setup

What does work: telnet and rsh from it, xntpd and ping (both ways)
and finally, if I change fstab again to mount the "old" /usr,
everything works again.

Please help.
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