Cisco UC540 incoming call problem

[Thai Huynh]

Hi everyone,

I have a problem with my UC540, below is my network diagram:

Internet---------887----------UC540

I have successfully configured UC540, incoming and outgoing call working perfect, but when I changed IP address on UC540's F0/0 which connected directly to 887VA then incoming call stop working??? outgoing call still work fine.

Example: I change F0/0 on UC540 from 192.168.1.200/24 to 192.168.1.201/24 then incoming call dead, if I change F0/0 ip back to 192.168.1.200/24 then incoming call work normal

Note: after int F0/0 has a new ip address, I have to restart the unit or it took long time for incoming call to work as normal.

Forgot to mention that I'm using SIP Trunk. Configure file attached with incoming call setting only for easy to troubleshooting.

Please help and thanks in advance.

Tim.

[mmoulson1 · Accepted solution]

Is this not just port forwarding on your 887? That is sending your SIP traffic to 192.168.1.200?

Hence when you change the IP incoming stops working. Outgoing continues to work as the UC540 can NAT out via the 887 so it's internal IP is not important for this call.

Hope that helps!

Matty