Cisco 520 Series, Software Configuration Manual

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Cisco Secure Router 520 Series Software Configuration Guide
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Chapter 12 Troubleshooting
ATM Troubleshooting Commands
•
To disable debugging, enter the undebug all command.
• To use debug commands during a Telnet session on your router, enter the terminal monitor
command.
Caution
Debugging is assigned a high priority in your router CPU process, and it can render your router unusable.
For this reason, use
debug commands only to troubleshoot specific problems. The best time to use debug
commands is during periods of low network traffic so that other activity on the network is not adversely
affected.
You can find additional information and documentation about the debug commands in the Cisco IOS
Debug Command Reference .
debug atm errors Command
Use the debug atm errors command to display ATM errors. The no form of this command disables
debugging output. Example 12-4 shows a sample output.
Example 12-4 Viewing ATM Errors
Router# debug atm errors
ATM errors debugging is on
Router#
01:32:02:ATM(ATM0.2):VC(3) Bad SAP received 4500
01:32:04:ATM(ATM0.2):VC(3) Bad SAP received 4500
01:32:06:ATM(ATM0.2):VC(3) Bad SAP received 4500
01:32:08:ATM(ATM0.2):VC(3) Bad SAP received 4500
01:32:10:ATM(ATM0.2):VC(3) Bad SAP received 4500
debug atm events Command
Use the debug atm events command to display events that occur on the ATM interface processor and to
diagnose problems in an ATM network. This command provides an overall picture of the stability of the
network. The
no form of this command disables debugging output.
If the interface is successfully communicating with the Digital Subscriber Line Access Multiplexer
(DSLAM) at the telephone company, the modem state is 0x10. If the interface is not communicating with
the DSLAM, the modem state is 0x8.
Example 12-5 shows an ADSL line that is up and training
successfully. Example 12-6 shows an ADSL line that is not communicating correctly. Note that the
modem state does not transition to 0x10.
Example 12-5 Viewing ATM Interface Processor Events—Success
Router# debug atm events
Router#
00:02:57: DSL: Send ADSL_OPEN command.
00:02:57: DSL: Using subfunction 0xA
00:02:57: DSL: Using subfunction 0xA
00:02:57: DSL: Sent command 0x5
00:02:57: DSL: Received response: 0x26
00:02:57: DSL: Unexpected response 0x26
00:02:57: DSL: Send ADSL_OPEN command.
00:02:57: DSL: Using subfunction 0xA
00:02:57: DSL: Using subfunction 0xA
00:02:57: DSL: Sent command 0x5