User guide

C-14
Cisco Media Gateway Manager 5.0 User Guide
OL-5461-02
Appendix C Troubleshooting
Topology Problems
C.4 Topology Problems
This section includes the following information:
C.4.1 Discovery Mechanism
C.4.2 Discovery Issues at Startup
C.4.1 Discovery Mechanism
Cisco MGM manages the PNNI network. The ILMITopoc process discovers the physical PNNI network
using SNMP protocol. All the discovered nodes are displayed in all the MGX NE GUIs such as
Configuration Center (CC), Diganostic Center (DC), Statistics Report (SR), Chassis View (CV) GUI.
Cisco MGM is notified of all subsequent changes in the network through traps for MGX nodes.
Once the ILMITopoc process discovers all the nodes, it sends all the nodes to topod process. Topod then
sends these nodes and trunks to other processes in Cisco MGM such as ooemc, NMServer, nts etc.
C.4.2 Discovery Issues at Startup
This section includes the following information:
• C.4.2.1 No Nodes Are Discovered
• C.4.2.2 Node Name Is Incorrect in Database
• C.4.2.3 Node IP Is Incorrect in Database
• C.4.2.4 Node Alarm Shown Incorrectly in Database
• C.4.2.5 Reachable Node Is Shown as Unreachable
• C.4.2.6 Cisco MGM State Is Incorrect
C.4.2.1 No Nodes Are Discovered
No nodes are in the Cisco MGM database.
Step 1 Verify that the nodes are ip reachable. Get the primary ip of the node by issuing the CLI commands
dspndparms and dspipif. Then check if the node is ipreachable from Cisco MGM.
This can be done by doing a ping <node ip address>.
Step 2 If the nodes are ip reachable from Cisco MGM, verify that the community strings of the gateway nodes
are correct.
This can be done by issuing the command dspsnmp on the switch CLI of the node that is not getting
discovered. Compare this community string with that in the node_info table. The community string in
the node_info table is encrypted. You will need to decrypt this string and verify it.