My Dec 5000/25 run netbsd 1.6.1 and is my dhcp/dns server. 
It has been a quite happy machine for a while.  In fact it has been 
running without a hitch since I had done some upgrading ("Peter C. 
Wallace" <pcw@mesanet.com>, do email me back with an address so I can 
pay for thge memory and the CPU.  Pretty please?) in it.  But, today, 
I went to do some stuff in it and could not ssh to it.  So, I decided 
to use the console.  This is what I got:

db> help
break           dmesg           p               show            watch
c               dwatch          print           sifting         write
call            examine         ps              step            x
callout         kill            reboot          sync
continue        machine         s               trace
d               match           search          until
delete          next            set             w
db> show
all             buf             map             page            uvmexp
arptab          event           ncache          pool            vnode
breaks          malloc          object          registers       watches
db> show all
callout procs
db> quit
No such command
db> reboot
syncing disks... panic: lockmgr: locking against myself
Begin traceback...
pid -2144880964 not found
End traceback...

dumping to dev 19,1 offset 50927
dump 40 39 38 37 36 35 34 33 32 sd0(asc0:0:0:0): asc0: timed out [ecb 
0x80aa3000
  (flags 0x1, dleft 1000, stat 0)], <state 5, nexus 0x80aa3000, 
phase(l 0, c 0, p
  0), resid 1000, msg(q 0,o 0) DMA active>
sd0(asc0:0:0:0): sync negotiation disabled
sd0(asc0:0:0:0): asc0: timed out [ecb 0x80aa3000 (flags 0x41, dleft 
1000, stat 0
)], <state 5, nexus 0x80aa3000, phase(l 0, c 0, p 0), resid 1000, msg(q 20,o 0)
DMA active> AGAIN
sd0: async, 8-bit transfers
i/o error


sd0(asc0:0:0:0): polling command not done
panic: scsipi_execute_xs
Begin traceback...
pid -2144800340 not found
End traceback...

dumping to dev 19,1 offset 50927
dump device not ready

What is going on here?  What was it trying to tell me?  HD is going 
boink?  I eventually turned it off for a bit and then rebooted it. 
Right now it seems to be happy once more, but I do not know for how 
long.  Suggestions?