End-to-End Troubleshooting

This chapter explains how to troubleshoot problems and/or conditions with the entire system from end-to-end, including the Cisco 6100, the Cisco 675 and the Cisco FireRunner.

Chapter Structure

Each subsection details the following information about end-to-end troubleshooting.

Problem Description - A short description of the problem or condition.
Probable Cause - A short discussion of the probable cause of the problem or condition.
Action - A step-by-step procedure for how to diagnose and solve the problem specified in the section.

Checklist of End-to-End Troubleshooting Procedures

The following table lists the end-to-end events described in this chapter, including the section name relative to the event.

Problem Description	Section Name
System trained but cannot pass data	"System trained but cannot pass data"

Table 6-1: End-to-End Troubleshooting Checklist

Problem Description Section Name

System trained but cannot pass data

"System trained but cannot pass data"

6.1 System trained but cannot pass data

Problem Description

The line is trained, but it cannot pass data over the subscriber connection.

Probable Cause

Incorrect ATM VPI/VCI addressing, failure in the end-to-end connection (beyond the Layer 1 ADSL connection), incorrect IP addressing at Layer 3.

Action

1. Ping the FireRunner from the Cisco 675, or vice-versa.

2. If ping is successful, and the node is not commissioned, loopback the network interface (NI) (or loopback logically at the ingress edge switch) and run a Bit Error Rate Test (BERT). See the "BERT Testing on the 6100" section in the "BERT Testing and System Set Up Verification" appendix for BERT test instructions. If node is already commissioned, running a BERT test will cause loss of service for all subscribers on that node.

3. If the BERT fails, replace the NI and run BERT again.

4. If the problem persists, contact Cisco TAC for further assistance.

5. If ping is unsuccessful, there may be an ATM and/or IP addressing problem.

6. Check the ATM VPI/VCI addressing:

Cisco 675 to the 6100 subscriber side VPI/VCI should match.
The 6100 to ingress ATM edge switch VPI/VCI should match (but are discrete from the 675 to 6100 addresses, as all ATM VPI/VCI addresses are of local significance only).
Ingress to transit, successive transit to transit ATM switch, and last transit to egress ATM switch VPI/VCI addresses should match.
Egress ATM switch to FireRunner VPI/VCI addresses should match.

If the ATM addresses match per the above checks, then a Layer 2 end-to-end connection path is established.

7. Check the IP addressing with a Layer 3 check in the 675 and FireRunner.

8. Note: there is no Layer 3 checking in the 6100.

The 675: check route tables - MAC to IP, default gateway, and subnet mask.

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