Checking port forwards

[lebenton]

Is there any way on the Quadro (which is behind a NAT router) to check
whether the required ports (in particular UDP 6000-6099 for RTP) has
been forwarded to the Quadro? ie. what indication does the Quadro give
me, to tell me that the RTP ports have been opened for it? I'm using
manual NAT traversal.



I'm asking this because I was at a client today. Their Quadro was
temporarily installed on a public IP awaiting a firewall to be
installed, and everything was working fine. Calls to 899 were normal.



Today the firewall was installed so I went today to move their Quadro
behind the firewall. Manual NAT traversal was setup, and SIP
registrations successful. So I made a test call to 899. No sound. As
the firewall was managed by another company, I asked nicely for them to
check over the port forward settings. Although I was assured the ports
were forwarded correctly, I was beginning to think otherwise.



So there I was, stuck at trying to figure out whether the RTP range was really forwarded or not.smileys/smiley5.gif



Suggestion anyone?



(I even assumed the internal static IP of the Quadro using my laptop,
and ran ShieldUp! tests from www.grc.com to see whether the port probes
were shown as Stealth or something else. But I wasn't sure whether this
is the right way to test...)

[voip advantage]

Check your system Events and look for the 'STUN' entries, it'll give you an indication of the detected ports and their status (Fail/Sucessful).

[davrays]

Thats right - if manual NAT traversal doesn't work, you can re-enable STUN and see what it detects (either in Events or on the "Status -> SIP Registration Status" pages). If ports (at least SIP port) are mapped correctly for manual NAT traversal, you should get "Full Cone NAT" detected.If there is another type of NAT detected - means NAT router works, but correct static port forwarding is not done. If there is Blocked UDP - means firewall just blocks packets at all.Edited by: davrays