Debugging a VNC link through routers
n.gilbert "at" soc.surrey.ac.uk
Fri Aug 27 09:09:00 2004
I have a Mac at home and my aunt, living 60 miles away, has a Mac in
her apartment. Both of us are on broadband, using different ISPs. I'd
like to use VNC to help her with problems she has from time to time
with using her Mac.
She has a ADSL modem/router which I hope I have set up to forward port
5900 to her Mac. I have an small local net, with an Apple Airport
wireless router and cable modem, which I have also set up to forward
port 5900. And I have checked that neither Mac has its firewall
software running. Her Mac is running a OSXvnc server.
However, I can't get vnc on my mac to 'see' hers. My next task is to
find out where the blockage is.
Is there some software that will identify not only that traffic on port
5900 is not getting through, but *where* the blockage is? I have tried
a traceroute (using mtr), which shows me that pings do get through, but
doesn't say anything about port 5900, and nmap, which reports that port
5900 is 'filtered' but doesn't say by what.