Re: My *reflector* seems to be half-working; any idea why?

Faux Joe (cutter@bronze.lcs.mit.edu)
Tue, 26 Mar 1996 10:04:20 -0500 (EST)


On Sat, 23 Mar 1996, Brian O'Shea wrote:

> >Environment:
> > Cornell reflector running on Sparc-20 w/Solaris 2.4
> > PC on Novell ethernet LAN running Windows 95 (with TCP/IP)
> > CU-SeeMe client (latest Cornell version)
> >
> >Problem:
> > I run the reflector software and it appears to comes up with no
> > errors; I can run refmon and connect to the reflector, do "who"s,
> > etc.
> >
> > When I connect from the PC, I get the inital reflector greeting
> > but it never completes the connection, and eventually times the
> > connection out -- even though refmon and the reflector log show I
> > did get in!
> >
> > If I can get the inital greeting screen, doesn't that mean
> > everything's hunky dory? Am I missing something?

> Hmm, Sparc 20 huh. I'll bet that's not your "personal" machine. I'll bet it
> does some routing duties too. Is it possible that it has multiple interfaces
> (IP addresses)?

Nope. Only one.

> Let me know if that fixes it...

The Pentium I'm running CU-SeeMe on has to go through a Cisco router
before it gets to the Sparc -- again, my question: if it can get the
opening "Welcome to this reflector!" message, why can't it create a
connection after that? Is the inital message a TCP connection, and
so should I be looking for a UDP block on that router? I ran "snoop" on
the Sparc and saw only UDP connections to port 7648, to wit:

Using device /dev/le (promiscuous mode)
jtpc -> dev UDP D=7648 S=7648 LEN=160
dev -> jtpc UDP D=7648 S=7648 LEN=44
dev -> jtpc UDP D=7648 S=7648 LEN=104
jtpc -> dev UDP D=7648 S=7648 LEN=56
jtpc -> dev UDP D=7648 S=7648 LEN=160
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev UDP D=7648 S=7648 LEN=56
jtpc -> dev UDP D=7648 S=7648 LEN=160
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev UDP D=7648 S=7648 LEN=56
jtpc -> dev UDP D=7648 S=7648 LEN=160
jtpc -> dev UDP D=7648 S=7648 LEN=160
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev UDP D=7648 S=7648 LEN=56
jtpc -> dev UDP D=7648 S=7648 LEN=160
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev UDP D=7648 S=7648 LEN=56
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev UDP D=7648 S=7648 LEN=56
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev UDP D=7648 S=7648 LEN=56
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev UDP D=7648 S=7648 LEN=56
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev UDP D=7648 S=7648 LEN=56
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev UDP D=7648 S=7648 LEN=56
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev ICMP Destination unreachable (Bad port)
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev ICMP Destination unreachable (Bad port)
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev ICMP Destination unreachable (Bad port)
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev ICMP Destination unreachable (Bad port)
dev -> jtpc UDP D=7648 S=7648 LEN=44
jtpc -> dev ICMP Destination unreachable (Bad port)

Clearly it's getting UDP through from PC <--> Sparc-20; I don't have a
camera on this PC, btw -- will that make a difference?

Thank you for your help!

/joe