Remote 3102 phone will not connect to NBX

[drehfeldt]

I want to connect a remote 3102 phone to our V3000 analog NBX on the main company LAN, but the phone is not connecting to the NBX.



The remote location is connected via T1 using Cisco 2801 routers. The remote LAN switch is a 3Com 4500-PWR and the local LAN switches are comprised of 3Com 4500-PWR and 3Com 5500-EI switches. The are no Voice VLAN's defined.



-> -> -T1- -> -> ->



-The remote phone was initially defined in the NBX and an extension assigned. It works on the local LAN.

-NBX is configured to use IP-on-the-fly.

-The remote phone has had IP address and NBX IP statically defined.

-The phone boots up and displays the following message:

"Connecting to NCP..."

"NCP IP 10.1.1.10"

Then the phone reboots after a couple minutes.



-A packet capture on the remote LAN and local Cisco router reveals that the phone is sending a UDP packet src port 2093 and dst port 2093, but the NBX is not responding.

-I can ping the remote phone from the local LAN and the NBX from the remote network.

-There is no other network traffic on this link yet

-There are no access control lists on the routers.

This message was edited by drehfeldt on 6-2-09 @ 9:28 AM

[merlin_1]

Sounds like you need to open up ports



2093

2094

205

2096

tcp port 1040

And it sounds like you have port 80 access already



On your network routers and allow traffic between the NBX and the tel . If the NBX will not respond then it is not getting the requests . You can trace the NBX side if you like as it will show you if the traffic is actually being recieved by the NBX . Another thing to check is Multicast . Make sure that is set up on the routers as well . we use it for conferencing , paging and time and date on the remote tel .

[drehfeldt]

All ports are open between the 3102 phone and NBX. I haven't configured multicast support on the WAN link, but understand that the phone should still connect to the NBX even if some multicast dependant functionality is missing, e.g. date/time, conferencing and paging.

[drehfeldt]

Thank you for the response Merlin. Where on the NBX can I trace the traffic received by the NBX? I already did a packet capture on the router interface connected to the main LAN on which the NBX resides. I don't see any packets from the NBX back to the phone. The NBX is connected to a 5500-EI which doesn't allow for port mirroring, so I can't get a packet capture off the NBX interface without moving the NBX network connection to another switch. (Which I may have to do, but want to avoid until necessary)

[drehfeldt]

The issue with connectivity was resolved by reconfiguring my GNS3 (www.gns3.net) Cisco WAN lab. I was using multiple physical NICS on my laptop and one older PCMCIA card just didn't work properly. I swapped it out for a different one and the phone started working. After that I was able to get the paging and conferencing working by configuring multicast routing along the path, which in my lab consists of physical 3Com layer 2/3/4 switches and virtual Cisco routers in GNS3.

[merlin_1]

Awesome !

Nice job !

[drehfeldt]

I forgot to mention initially that my test environment wasn't a full production LAN, but part production and part virtualized. The 3Com 4500-PWR switch on one physical NIC was used to power and provide connectivity for a 3102 phone and computer from the "branch" office. This connectivity ran through a virtualized T1 WAN using GNS3 on my laptop with the switch connecting to a virtualized router. At the other end of the virtualized WAN that router connected to a second physical NIC on my laptop and was bridged to the production network where the NBX resides. I eventually discovered that one of the physical NICS, and older PCMIA card, was faulty and not passing all of the traffic. Once replaced, the 3102 phone connected to the production NBX over the virtualized WAN.



Despite the hassle with my bad PCMCIA card, this environment offered several benefits: low cost and risk for testing router configurations, the ability to test a WAN connection without paying for one, the ability to capture all data traffic running over any of the virtual links for analysis, and geek points with the rest of the team.



I hope this helps someone else.



www.gns3.net

This message was edited by drehfeldt on 6-12-09 @ 7:30 PM