[comp.protocols.tcp-ip] Help with SLIP under SunOS 4.0

verber@pacific.mps.ohio-state.edu (Mark A. Verber) (08/03/89)

I picked up a copy of the stream based slip for SunOS 4.x recently
from neat.ai.toronto.edu.  I know I must have done something stupid
but I can't figure out want it was (and since the machine I am running
as my slip server is also servicing 14 diskless clients I can't afford
to do alot of testing.).  I was hoping someone might be able to
recognize my problem and save me alot of problem.

The primary symptom is that as soon as sliplogin is run, slip_open
seems to be repeatedly called.  For example, the following messages
were generated in a period less than a minute from a *single* sliplogin:

	slip0: coming up
	slip1: coming up
	slip2: coming up
	slip3: coming up
	slip4: coming up
	slip: cannot allocate interface (NSLIP is 5)
	slip: cannot allocate interface (NSLIP is 5)
	slip: cannot allocate interface (NSLIP is 5)
	slip: cannot allocate interface (NSLIP is 5)
	slip: cannot allocate interface (NSLIP is 5)
	slip: cannot allocate interface (NSLIP is 5)

My configuration is a Sun 4/280 running SunOS 4.0 w/ the yapt 5.5c
patches installed.  I am using ttyb which has flags set to 3.  I was
using a IBM-AT running ka9q as a slip client.  One oddity was that
while I got these messages I was having no problem using slip to get
to/from the PC running ka9q.  The initual slip connection seemed to be
working fine.

Another symptom is when a HUP was sent to sliplogin my machine crashed
with the following output:

	slip4: going down
	BAD TRAP
	syslogd: Data fault
	kernel read fault at addr=0xc, pme=0x0
	Bus Error Reg 80<INVALID>
	pid=303, pc=0xf80b72b0, sp=0xf80d0b40, psr=0x400cc6, context=8
	g1-g7: c00, 400ce0, 0, 0, 0, f80e9000, f80e9000

Any ideas what I did wrong?  I have check twice make sure my copy of
sliplogin and tty_slip were the same as the one on neat.  Seems to be
fine.  I believe I followed all the instructions in the README.

--- Mark Verber
    verber@mps.ohio-state.edu
    1-614-292-8002

verber@pacific.mps.ohio-state.edu (Mark A. Verber) (08/07/89)

Thanks to everyone who responded to my query.  In the end I figured things
out myself (just after posting of course).  The problem with slip_open
being called multiple times was that my shell hadn't let go of the tty
and was still trying to write... sigh.

---mark verber