VOICE: IOS SIP Trunk 403 Forbidden error?
Thu, Oct 20 2011 09:29
I spent a few hours on this one. Here is the situation:
Cisco 2621XM has a SIP trunk setup between itself and an online SIP trunk provider called voipfone.co.uk. The trunk is up and established:
I cal make calls outbound to their ECHO test number on 152 and their COURTESY number 155. I can also take incoming calls to my SIP number 057XXXXXXXX. This all looks good. What I can't do however is call anything outbound on any number other than those test numbers. After a few hours I figured this had to be something to do with authentication. Basically my reasoning was that maybe those service numbers (152/155) might just be globally allowed (FREE to use) numbers. Once I try to access a paid number I'll need to be authenticated.
So I quickly ran up a debug for the SIP call.
After making a new test call to an external number I picked up on the dreaded SIP/2.0 403 Forbidden error in the debug logs:
So there it was, my authentication error, but how do I fix it? I looked under the sip-ua configuration and found my credential and authentication statements. I removed them and put them back again, still not working. Clearly this was something else. After using the context help I found the 'calling-info' command. This command had a few arguments that looked interesting and one of them was specifically for calls gong to and from the PSTN...so I drilled into it.
After entering this command my trunk started to allow outbound calls. Also the debug showed that the 403 Forbidden had gone away.