Router 4531 IOS XE Static NAT issues

[remi-reszka]

Hello Experts,

I'm having troubles with newly bought router 4531 running IOS XE version: isr4300-universalk9.03.16.02.S.155-3.S2-ext.SPA.bin. I have a static NAT for SIP UDP 5060 and RTP ports 10000 to 10020. What happens is that the UDP port translation does not take effect, the NAT on this IOS XE ignores the static NAT configuration and opens dinamic ports instead.

I have the same configuration on 2800 and 2900 series routers and no issues, I register SIP mobile extention and can communicate with SIP office extensions.

While applying static NAT for 5060 port I get and error that this NAT port is being used (not having this issue on 2800 or 2900 routers) and first I have to remove PAT config, apply static NAT for UDP 5060 and then re-apply the PAT. 

Anybody had similar issues or could advise me what is wrong with this platform?

Thanks and best regards.

Remi

[Shaunak]

I second Philip here, for VOIP applications and the kind of port range and protocols it requires to be NATted it's easier to pull it off with a new IP address.

Thanks,

Shaunak

[remi-reszka]

Thanks Philip, I will try getting a new IP address however before that I will run a test on a current IP address. Will let you know the results.

Best regards,

Remi

[stuart.pannell]

Hi, did you get your issues resolved? I am seeing similar issues with an ISR C1112 and thought it may have been NAT or SIP ALG related. Have you tried disabling SIP ALG by using the "no ip nat service sip udp 5060" and "no ip nat service sip tcp 5060" commands?

I have taken the configuration from a Cisco 887VA running IOS 15.x and applied it to my ISR C1112 running IOS XE and it does not work!