DEC Alpha Multia/UDB box ran NetBSD 1.4.1 okay.
Needed to upgrade.  Tried custom 3.0.1 kernel with
1.4.1 userland.  No console (rs-232), no rs-232.
Could get in via Ethernet.

Thinking maybe something in userland was somehow hosing rs-232,
I upgraded everything to 3.0.1, even the boot blocks.
Now there is no console and no Ethernet.  Okay, maybe my custom
kernel is hosed, so I installed the 3.0.1 GENERIC kernel.
Still nothing.  Doesn't even respond to ping.

NetBSD 3.0.1 (GENERIC) #0: Thu Jul 13 20:49:56 UTC 2006
        builds@pb:/home/builds/ab/netbsd-3-0-1-RELEASE/alpha/200607131826Z-obj/h
ome/builds/ab/netbsd-3-0-1-RELEASE/src/sys/arch/alpha/compile/GENERIC
(PCI ISA), 167MHz, s/n
8192 byte page size, 1 processor.
total memory = 32768 KB
(2368 KB reserved for PROM, 30400 KB used by NetBSD)
avail memory = 21432 KB
mainbus0 (root)
cpu0 at mainbus0: ID 0 (primary), LCA-2 (21066)

[ ... ]

siop0 at pci0 dev 6 function 0: Symbios Logic 53c810 (fast scsi)
siop0: interrupting at isa irq 11
scsibus0 at siop0: 8 targets, 8 luns per target
sio0 at pci0 dev 7 function 0: Intel 82378ZB System I/O (rev. 0x03)
tlp0 at pci0 dev 8 function 0: DECchip 21040 Ethernet, pass 2.3
tlp0: interrupting at isa irq 15

[ ... ]

isa0 at sio0
lpt0 at isa0 port 0x3bc-0x3bf irq 7
com0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
com0: console
com1 at isa0 port 0x2f8-0x2ff irq 3: ns16550a, working fifo

[ ... ]

pcmcia1 at pcic0 controller 0 socket 1
stray isa irq 3
stray isa irq 4
fd0 at fdc0 drive 0: 1.44MB, 80 cyl, 2 head, 18 sec
pcic0: controller 0 detecting irqs with mask 0xdeb8:stray isa irq 5
stray isa irq 5
stray isa irq 5
stray isa irq 5
stray isa irq 5; stopped logging
stray isa irq 14
stray isa irq 14
stray isa irq 14
stray isa irq 14
stray isa irq 14; stopped logging
 none
pcic0: no available irq; polling for socket events
Kernelized RAIDframe activated
scsibus0: waiting 2 seconds for devices to settle...
scsibus1: waiting 2 seconds for devices to settle...
sd0 at scsibus0 target 0 lun 0: <TOSHIBA, MK1824FBV, 805B> disk fixed
sd0: 335 MB, 4195 cyl, 4 head, 41 sec, 512 bytes/sect x 687980 sectors
sd0: sync (100.00ns offset 8), 8-bit (10.000MB/s) transfers
root on sd0a dumps on sd0b
root file system type: ffs


At this point it appears to hang.  Nothing further is printed to the
rs-232 console, does not respond to return, ^C, BREAK, etc.  Does
not respond to ping.

I tried booting single-user, it printed 3 more lines before hanging:

root on sd0a dumps on sd0b
root file system type: ffs
WARNING: preposterous clock chip time
 -- CHECK AND RESET THE DATE!
stray isa irq 4

Are all those "stray isa irq" messages something to worry about?

The Ethernet could be some configuration quirk, but the console should
work, especially in single-user mode.

At this point I'm pretty much out of ideas.  There seems to something
wrong with 3.0.1 but I'm not sure what.  I can't search the archives
since this machine is in the IP path to the internet.  I do have 3.0.1
sources and could try another custom kernel if I knew what to fix.

Please cc me on any responses.  Thanks.