SIP 2.0 : 403 Forbidden, cause code 21 in voice gateway for certain calls

[UdayChakraborty42238]

Hi All

While calling certain external numbers, the calls get rejected on the voice gateway (ISR 4400 series) with cause code 21. At the same time few calls go through successfully. Below is the call flow.

SFB call control ---> SIP voice gateway -----> PSTN

IOS version: 16.6.6

Please provide your valuable inputs.  

Regards

Uday

[Roger Kallberg]

Your likely not to get all that much help without providing debug output for a working and failing call. We're after all not magicians.

Start with collect debug ccsip message output of both calls and attached it as files to the post.