Troubleshooting guide

Table of Contents
Cisco DSL Router Configuration and Troubleshooting Guide
View Your Configuration................................................................................................................22
Configuration.........................................................................................................................................22
Troubleshoot Your Configuration..........................................................................................................23
Cisco DSL Router − PPPoA with a Dynamic IP Address.....................................................................23
Tasks to Perform....................................................................................................................................24
Configuration.........................................................................................................................................24
Troubleshoot Your Configuration..........................................................................................................25
Cisco DSL Router – PPPoA with a Static IP Address...........................................................................26
Tasks to Perform....................................................................................................................................26
Configuration.........................................................................................................................................26
Troubleshoot Your Configuration..........................................................................................................28
PPPoA Implementation Options............................................................................................................28
PPPoE Implementation Options for the Cisco DSL Router Acting as a PPPoE Client........................28
PPPoA – Troubleshooting.....................................................................................................................29
Determine the Layer to Troubleshoot....................................................................................................29
Layer 1 Issues........................................................................................................................................29
Is the carrier detect (CD) light on the front panel of the Cisco DSL Router on or off?..................30
Is your ISP using a DSLAM that supports the Alcatel chipset?.....................................................30
Is the DSL port on the back of the Cisco DSL Router plugged into the DSL wall jack?...............30
Is the ATM interface in an administratively down state?...............................................................30
Is the cable pinout correct?..............................................................................................................30
If you are using a Cisco 827 as your DSL Customer Premises Equipment (CPE), do you have
the correct power supply for the Cisco 827?...........................................................................31
Is the DSL operating−mode correct?..............................................................................................31
Is the circuit tested/provisioned correctly?......................................................................................32
Layer 2 Issues........................................................................................................................................32
Do you have the correct Permanent Virtual Circuit (PVC) values (VPI/VCI)?.............................32
Are you receiving data from your ISP?...........................................................................................33
Is PPP negotiating properly?...........................................................................................................34
How do I know if my PAP username and password are correct?...................................................37
How do I know if my CHAP username and password are correct?................................................38
How do I know when PPP authentication is successful?................................................................38
Related Information...............................................................................................................................39
Contact the Cisco Technical Assistance Center.....................................................................................39
RFC1483 Bridging Implementations.....................................................................................................40
PPPoA Online Form.............................................................................................................................40
Record Information from the ISP..........................................................................................................41
Record Information About Your Network.............................................................................................41
Choose Your Next Step.........................................................................................................................41
Step−by−Step Configuration of PPPoE with a Dynamic IP Address....................................................42
Step−by−Step Configuration.................................................................................................................42
Connect the Cisco DSL Router and Your PC.................................................................................42
Start and Set Up HyperTerminal.....................................................................................................42
Clear Existing Configurations on the Cisco DSL Router................................................................43
Configure the Cisco DSL Router....................................................................................................43
View Your Configuration................................................................................................................45
Configuration.........................................................................................................................................46
Cisco DSL Router Configuration and Troubleshooting Guide
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