Troubleshooting guide

12-9
ATM and Layer 3 Switch Router Troubleshooting Guide
OL-1969-01
Chapter 12 Troubleshooting Layer 2 Interfaces
Troubleshooting Layer 2 Switching
Step 11 Use the show epc if-entry interface FastEthernet interface entry GigabitEthernet
interface.subinterface command to display the CAM table entry.
Switch# show epc if-entry interface FastEthernet 12/0/1 entry GigabitEthernet 11/0/1.1
IF Entry for GigabitEthernet11/0/1.1 on FastEthernet12/0/1
Mac(hex) - 00:90:21:dd:dd:dd
isMyInteface : False isSubInterface : True
Status Up Broute VC - 662 Bcast VC - 747
Netmask: 32
FEC disabled
ISL, Vlan 1
State : Forwarding
Bridge-Group enabled
IP routing off bridging on
IPX routing off bridging on
Appletalk routing off
In Encapsulation:
ICMP Redirect disabled Unreachable disabled
IP Multicast disabled: ttl-threshold: 0
Step 12 Confirm the following:
• Brouter VC status is up.
• State is forwarding.
• All routing protocols, IP, IPX, and Appletalk are off.
Step 13 Use the same command again but with the interface entries reversed.
Switch# show epc if-entry interface GigabitEthernet 11/0/1.1 entry FastEthernet 12/0/1
IF Entry for FastEthernet12/0/1 on GigabitEthernet11/0/1
Mac(hex) - 00:90:21:cc:cc:cc
isMyInteface : False isSubInterface : False
Status Up Broute VC - 622 Bcast VC - 747
Netmask: 32
FEC disabled
Trunking Disabled
State : Forwarding
Bridge-Group enabled
IP routing off bridging on
IPX routing off bridging on
Appletalk routing off
In Encapsulation:
ICMP Redirect disabled Unreachable disabled
IP Multicast disabled: ttl-threshold: 0
Step 14 Confirm the following:
• Brouter VC status is up.
• State is forwarding.
• All routing protocols, IP, IPX, and Appletalk are off.
Troubleshooting Layer 2 connections differs from troubleshooting Layer 3 connections in the following
ways:
• MAC entries are learned and not downloaded from route processor.
• Not all Ethernet processor interface CAM entries in the same bridge group contain all entries.
• You must verify the status of the Broute and the Bcast VC on both the ingress and egress ports.