Troubleshooting guide

9-9
ATM and Layer 3 Switch Router Troubleshooting Guide
OL-1969-01
Chapter 9 Troubleshooting CES Connections and Network Clocking
Troubleshooting Network Clocking
• A route processor failure caused the network clock module to fail.
• The network clock module is in holdover mode.
The following are minor alarm conditions:
• A switchover from the primary clock source to the secondary clock source occurred.
• A loss of a single reference to the network clock source occurred while the network clock source
was set to free running.
Checking the Network Clock Source Configuration
Use the following commands to troubleshoot the network clock source configuration:
Follow these steps to troubleshoot the network clocking configuration on an ATM switch that does not
have the network clock module installed:
Step 1 The network clock type configured on the switch must match the current clock source. Use the
show network-clocks command to display the network clocking configuration.
Switch# show network-clocks
clock configuration is NON-Revertive
Priority 1 clock source: ATM0/0/0(down)
Priority 2 clock source: No clock
Priority 3 clock source: No clock
Priority 4 clock source: No clock
Priority 5 clock source: System clock
Current clock source:System clock, priority:5
Step 2 Check the clock configuration field to confirm that the clock switchover mode is configured correctly.
If it is not, use the network-clock-select command to correctly configure the clock switchover mode.
Step 3 Check the clock source fields to confirm that the desired clock sources are configured. Use the
network-clock-select command to configure the clock sources. See Table 9-1 for a list of network clock
source features.
Step 4 Check the status of the clock sources. If the clock source is listed as “down,” check the interface status
using the procedure described in Chapter 5, “Troubleshooting Switch Router ATM
Interface Connections.”
Note Once the clock problem is solved, reconfigure the network clock using the network-clock-select
command to make sure that the primary clock becomes the present clock source. The no shutdown
command does not affect the network clock source status.
Command Purpose
show network-clocks Confirms the network clock
configuration.
debug ports netclock Debugs network clock events.
no debug all Turns off all debugging.