Hi there,
I got a Cisco ASA sitting between Cisco CUCM and SIP Service provider. There is 1-to-1 NATing between Intern IP address of the CUCM and a separate extern IP address. When a SIP call is initiated from inside to outside, the SIP Headers contains the Intern/Local IP address of the Cisco CUCM instead of the NATed Extern/Public IP address.
I have double checked the NAT and ACL rules and the are correct. I have tried to turn on/off SIP Inspection in the ASA, but it didn't help.
Why the SIP Headers aren't modified while passing through Cisco ASA (changing the Intern IP address from local IP address to Public IP address)?
Any suggestion or advice will be helpful.
Thanks & regards,
Sam Saul