Symptom: It is always busy tone when IAD users dial.
1. Check the information of registered users on Eudemon2100, and it is found that the IP addresses of users are all 0, indicating that they fali in registration.
2. Check the configuration of Eudemon2100, and it is normal.
3. Enable debug sbc mgcp packet all command at Eudemon2100 to check the interaction of registration packets. It is found that Eudemon2100 receives the registration information of IAD users, and forwards the information to C&C08, but C&C08 does not respond.
4. Check the route from Eudemon2100 to C&C08, and NE40 serves as L2 switch in the network, so the route works well.
5. Capture packets at inbound direction of uplink port from NE40 to CC08, and it is found that no MGCP packet enters the port. At this time, it is made sure that the problem is caused by that tha tC&C08 does not respond to the registration information of IAD users.
Change the configuration of C&C08, and IAD users could register and call out normally.
1. The configuration of Eudemon2100 is false.
2. Eudemon2100 as signaling proxy fails to forwarding registration information.
3. IAD or the Softswitch is configured falsely.
4. The route is responsible for that interaction packets cannot transmit normally.
The case is caused by the third possibility.