Core Issue
The isdn bind-l3 ccm-manager command backhauls (tunnels) ISDN Layer 3 (L3) and higher layers to the Cisco CallManager. PRI/Q.931 signaling backhauls signals (Q.931 and higher) for processing from a PRI trunk that physically connects a Media Gateway Control Protocol (MGCP) gateway to a MGCP call agent. The ISDN lower layer information (Q.921 and lower) terminates and is processed on the gateway. The L3 information (Q.931 and higher) is transported over TCP to the Cisco CallManager (MGCP call agent).
This problem is discussed in Cisco bug ID CSCed15644.
Resolution
To resolve this issue, perform one or more of these steps:
- Reload the gateway.
- Manually add the isdn bind-l3 ccm-manager command to the gateway configuration.
- If the ccm-manager config command is configured, remove it from the configuration and set the missing command (isdn bind-l3 ccm-manager) under the serial interface. Then, save this configuration to the Nonvolatile RAM (NVRAM), and reload.