Subject: Sun 3/50 Networking Problems
To: None <port-sun3@NetBSD.ORG>
From: Curt Sampson <>
List: port-sun3
Date: 12/17/1995 20:37:24
This isn't really anything to do with NetBSD, but I dug through
the comp.sys.sun groups and noticed that Sun 3s don't seem too
popular there anymore. :-) I suspect this may be one of the best
sources of Sun 3 information on the Net.

I've just recently purchased a Sun 3/50 which I hope to get NetBSD
up and running on one day. I don't have a lot of time at the moment,
however, so I thought I'd just chuck up the Xkernel-2.0 package,
which is a minimal SunOS 4 kernel and Xserver configuration, and
use this beastie as an xterm at the moment.

Unfortunately, I'm having some strange networking problems. Sometimes
when I boot, tftp goes for a bit and then slows down to a packet
every three seconds or so. Sometimes it will pick up to normal
speed again, or at least gives a burst of a few packets, somtimes
not. I've tcpdumped the output, and it's always seems to be the
Sun that delays sending the acknowledgement for a few seconds for
the previous tftp data packet from the server. After I finally get
up an running, it's rare for the xdm login window ever to come up;
I get a lot of TCP packets from the Sun that have a byte missing
off the end, according to tcpdump:

    04:16:43.741523 truncated-ip - 1 bytes missing!spartan.6000 > \
	cynic.4483: . 1480:2940(1460) ack 69 win 4096

I've run all of the ethernet tests in the prom for a couple of
hundred cycles each, and get no error messages. I get the same
problems whether I'm using the built-in thinnet port or 10base-T
via a known working transceiver.

Any thoughts?

And while I'm here, how well does the Sun3 port work on machines
with 4MB of RAM? It sounds a bit painful to me. Is there any easy
(and cheap!) way to upgrade a Sun 3/50 to 8MB or 12 MB of RAM?


Curt Sampson		Info at
Internet Portal Services, Inc.	
Vancouver, BC   (604) 257-9400		De gustibus, aut bene aut nihil.