Troubleshooting Cisco UE Startup

You might experience situations in which the basic IP communication between the host router and the Cisco UE module fails even after proper configuration of the host router. You can identify such a problem by looking for waiting events such as those shown in an extract of the installation output in Example 19-20.

Example 19-20. Installation Output Extract Showing Cisco UE Waiting for the Host Router

==> only eth0 exists, we must be running on an AIM
==> only eth0 exists, we must be running on an AIM

Router communications servers initializing...complete.
Waiting for IOS to register IP address. 
- waited 10 seconds... 
Waiting for IOS to register IP address.
 - waited 20 seconds...

Cisco UE is waiting for commands from the Cisco IOS router to configure Cisco UE with its IP address and default gateway parameters so that Cisco UE can communicate with the rest of the network. However, it is not receiving any response from the router. This process of configuring the Cisco UE module through the host Cisco IOS router uses the RBCP, as discussed in Chapter 3. There might be some situations in which you have to troubleshoot this protocol exchange between the host router and Cisco UE.

When Cisco UE successfully communicates with the router using RBCP and receives its IP parameters, you see the message shown in Example 19-21 on the Cisco UE console during application bootup.

Example 19-21. Correct Response from the Host Router to Cisco UE

==> only eth0 exists, we must be running on an AIM
==> only eth0 exists, we must be running on an AIM
Router communications servers initializing...complete.
IOS IP Address Registration complete. 

The following few sections discuss troubleshooting problems during application bootup and communication issues between Cisco UE and the host router.

Checking Console Output on the Cisco UE Hardware

If you are having a problem opening a session to the Cisco UE module, or you don't see any output on the console, you can use the following command to check the console messages on the Cisco UE module without needing to open a session to the Cisco UE module:

 router#test service-module service-engine slot/unit console

By default, this command displays the most recent 80 lines stored in the console buffer. However, it is possible to specify an offset of greater or less than 80, or to view all the messages stored in the console buffer.

Checking the RBCP Communication

To check the RBCP status on the Cisco UE module from the router, you can use the following test command:

router#test scp ping slot

This command sends a ping to the Cisco UE module as an RBCP message using operational code (opcode) 0x11. If the RBCP process on the Cisco UE module is up and running, the ping succeeds, and the output of the test command should look as shown in Example 19-22.

Example 19-22. Testing Ping Output

router#test scp ping 3
pinging addr 3(0x3)
assigned sap 0x4
addr 3(0x3) is alive

 

Debugging the RBCP Communication

There are situations in which you have to troubleshoot the RBCP messages between the Cisco UE module and the router. One situation is when the interface configuration has been verified but you still cannot ping the Cisco UE module.

First, check the interface's status and ensure that the interface and line protocol are up, as shown in Example 19-23.

Example 19-23. Checking the Status of the Service-Engine Interface

router#show interfaces service-engine 1/0
Service-Engine1/0 is up, line protocol is up 
 Hardware is I82559FE, address is 0001.b912.f510 (bia 0001.b912.f510)
 Interface is unnumbered. Using address of FastEthernet0/0 (1.3.6.29)

Next, you should verify the RBCP state machine status on the router, as shown in Example 19-24. The Cisco UE module should be in steady state for proper operation. The example shows the status of service-engine 1/0.

Example 19-24. Checking the Status of the RBCP State Machine

ccme#service-module service-Engine 1/0 status
Service Module is Cisco Service-Engine1/0
Service Module supports session via TTY line 33
Service Module is in Steady state 
cisco service engine 1.0

If you are still unable to ping the Cisco UE module IP address, troubleshoot the RBCP messages exchanged between the Cisco UE module and the host router. Table 19-3 describes the flags and how they are used for the scp-tx message. scp-tx stands for Switch Communication Protocol transmission, meaning that the router transmits this message to the Cisco UE module.

Table 19-3. Flags for the scp-tx RBCP Message

Opcode	Action	Action Description	Type	Interface Description
0054	01	Configure	01	Internal IP address
0054	00	Unconfigure	01	Internal IP address
0059	01	Configure
0059	00	Unconfigure

Table 19-4 describes the flags and how they are used for the scp-rx message, which is a "Switch Communication Protocol" message the router receives from the Cisco UE module.

Table 19-4. Flags for the scp-rx RBCP Message

Opcode	Type	Type Description
0054	01	Internal IP address rejected
0054	02	Internal IP address OK
0054	03	External IP address rejected (not used for NM-CUE)
0054	04	External IP address OK (not used for NM-CUE)
0059	00	Default IP gateway OK
0059	01	Default IP gateway rejected

The output of debug scp all is shown in Example 19-25. An IP address (192.168.0.2/255.255.0.0) is being configured on the Ethernet interface of the Cisco UE module.

Example 19-25. IP Address RBCP Message Being Sent from the Router

router#debug scp all
router(config-if)#service-module ip address 192.168.0.2 255.255.0.0
router(config-if)#
*Mar 2 18:07:24.673: scp-tx: SA:0F/01 DA:01/01 Op:0054 Sq:13C7 Ln:000A I:00
*Mar 2 18:07:24.673: 000: 01 01 C0 A8 00 02 FF FF 00 00 .....L....
*Mar 2 18:07:24.681: scp-rx: SA:0E/01 DA:0F/01 Op:0054 Sq:13C7 Ln:000A I:01
*Mar 2 18:07:24.681: 000: 02 00 00 00 00 00 00 00 00 00

The output shows that the scp-tx message transmitted has the Source Address (SA) field set to 0F/01, which indicates that the message originated from the router. The Destination Address (DA) field is set to 01/01, which indicates that the Cisco UE module is present in slot 1. The opcode of 0054 indicates that this is an IP address configuration. The sequence number (Sq) field is 0B26, and the length of the payload is 10 bytes.

The first parameter on the second line is the type, and the second parameter is the action. In the message, the type is 01 and the action is 01, indicating that the Cisco UE module interface is being configured. The next 8 bytes are the IP address and subnet mask.

In the output shown for the scp-rx message, the SA field is set to 0E/01, indicating that it originated from the Cisco UE module in slot 1. The DA field is set to 0F/01, indicating that the message is destined for the router. The Opcode and Sq fields are the same as in the scp-tx message. The Type field in the second line is set to 02, which means that the Cisco UE module IP address was set properly. The rest of the parameters have no significance.

Example 19-26 shows the Cisco UE module's default-gateway parameter being set.

Example 19-26. Default Gateway Configuration RBCP Message

router#debug scp all
router(config)#int content-engine 1/0
router(config-if)#service-module ip default-gateway 192.168.0.1
1d23h: scp-tx: SA:0F/01 DA:01/01 Op:0059 Sq:0B28 Ln:0005 I:00
1d23h: 000: 01 C0 A8 00 01 .....
1d23h: scp-rx: SA:01/01 DA:0F/01 Op:0059 Sq:0B28 Ln:0005 I:01
1d23h: 000: 00 FF FF FF E0

The debug output of the scp-tx message shows that the opcode is different. The value 0059 indicates that this message pertains to the IP default-gateway configuration parameter. The length of the payload is 5 bytes. The payload is shorter than the scp-tx message shown in Example 19-25 (it's 5 bytes in Example 19-26 and 10 bytes in Example 19-25), because no subnet mask is associated with the default gateway IP address. The action flag is set to 01, which indicates that the default gateway is being configured. In the output of scp-rx message, the action flag is set to 00, confirming that the configuration of the IP default gateway address was successful.

Table 19-5 summarizes some of the common problems encountered when installing and configuring a Cisco UE module, and possible solutions to those problems.

Table 19-5. Common Installation Problems and Resolutions

Problem	Possible Reason	Possible Solution
You can't open a session into the NM-CUE.	The TTY line associated with the NM-CUE is already occupied.	Use the service-module service-engine slot/port session clear command, or clear line xx to clear the TTY line.
The session, when invoked, results in a connection refused error message.	The TTY line associated with the NM-CUE is occupied.	Configure no exec under the TTY line associated with the NM-CUE. This prevents the line from being unavailable because of a rogue EXEC process.
Service module commands do not seem to take effect.	The service module status might not be in steady state. RBCP configuration messages go through only when the service module is in steady state.	It is possible that the service module is not responding. Try reloading the service module. If that doesn't work, use the reset command.
You can't ping the internal address when using the IP unnumbered scheme.	The IP route table is incorrect.	When using ip unnumbered, always remember to add a static route pointing toward the service-engine interface.
IOS doesn't let you change or remove the IP address of the CE NM interface.	The default gateway of the CE NM must be pointing to the same IP subnet as the interface being changed or removed.	First remove the IP default gateway from under the service-engine interface. Then change the interface's IP address and add back the IP default gateway.
You can set the speed of the terminal line from the router side, but you can't see any CLI for doing the same on the CE side.	There is no CLI to change the speed. The speed is hard-set to 9600, 8-N-1 on both the IOS and CE sides. Even though IOS allows you to change the speed settings, this doesn't take effect.

Troubleshooting the Initialization Wizard