Troubleshooting guide

2-3
ATM and Layer 3 Switch Router Troubleshooting Guide
OL-1969-01
Chapter 2 Troubleshooting Tools
Using Diagnostic Commands
debug Commands
The debug privileged EXEC commands provide a wealth of information about the traffic seen (or not
seen) on an interface, error messages generated by nodes on the network, protocol-specific diagnostic
packets and cells, and other useful troubleshooting data.
Caution Be careful when using debug commands. Many of these commands are processor intensive and can
cause serious network problems (such as degraded performance or loss of connectivity) if they are
enabled on an already heavily loaded switch router. When you finish using a debug command,
remember to disable it with its specific no debug command (or use the no debug all command to
turn off all debugging).
Appendix A, “Debugging a Switch Router,” provides an overview of debug commands, including how
to use them when you are troubleshooting the switch router.
In many situations, third-party diagnostic tools can be more useful and less intrusive than using debug
commands. For more information, see the “Third-Party Troubleshooting Tools” section on page 2-4.
ping Commands
To check host reachability and network connectivity, use the ping user EXEC or privileged EXEC
command. This command can be used to confirm basic network connectivity on IP networks.
For IP, the ping command sends Internet Control Message Protocol (ICMP) echo messages. If a station
receives an ICMP echo message, it sends an ICMP echo reply message back to the source.
Table 2-2 show Command Conversion
Release 12.0(5)W5(13d) and Earlier show Command Syntax Release 12.0(10)W5(18) and Later show Command Syntax
show epc if-entry interface {fastethernet |
gigabitethernet} slot/subslot/port all
show controllers {fastethernet | gigabitethernet}
slot/subslot/port if-entry all
show epc if-entry interface {fastethernet |
gigabitethernet} slot/subslot/port entry {fastethernet |
gigabitethernet} slot/subslot/port
show controllers {fastethernet | gigabitethernet}
slot/subslot/port if-entry entry {fastethernet |
gigabitethernet} slot/subslot/port
show epc freecam interface slot/subslot/port show controllers {fastethernet | gigabitethernet}
slot/subslot/port freecam
show epc ipmcast groupaddr interface {fastethernet |
gigabitethernet} [cam {0 | 1}]
show controllers {fastethernet | gigabitethernet}
slot/subslot/port ipmcast groupaddr [cam {0 | 1}]
show epc ipmcast groupaddr all interface {fastethernet |
gigabitethernet}
show controllers {fastethernet | gigabitethernet}
slot/subslot/port ipmcast groupaddr all
show epc ipmcast groupaddr detail interface {fastethernet
| gigabitethernet}
show controllers {fastethernet | gigabitethernet}
slot/subslot/port ipmcast groupaddr detail
show epc counters show controllers c8500 counters
show epc queuing show controllers c8500 queuing