[Config] Problem passing SIP through Cisco 2821
We need help resolving a SIP Trunk Problem. We have a data T1 with Ethernet handoff. Our SIP trunks work fine when our Asterisk PBX is attached to the Ethernet handoff. We can pass internet traffic through our Cisco 2821 Router. We have the handoff coming in on port 0/0 of our our Cisco 2821 Router and can pass Internet traffic to port 0/1. We cannot pass SIP traffic to port 0/1 even when the access lists inbound and outbound on both ports permit any.
Our router is Cisco 2821 Integrated Services Router.2821 SEC BUNDLE AIM-VPN-EPII-PLUS ADV IP SERV. Security bundle with Cisco IOS advanced IP services
Is there something special that needs to be done to make this work? Any advice would be much appreciated.
Since you have security bundle, add a sip inspect command and make sure UDP 5060 is open in both directions in your ACL. Do you see the NAT translation for the outbound traffic from the PBX? Another set of commands you can add are
nat symmetric role active
Since you may not have the voice bundle the below command may not be available to you
voice service voip
allow-connections sip to sip