Troubleshooting guide

Contents
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ATM and Layer 3 Switch Router Troubleshooting Guide
OL-1969-01
Troubleshooting the ACL Daughter Cards 10-47
CHAPTER 11 Troubleshooting Layer 3 Network Connections 11-1
Overview of Layer 3 Switching 11-1
Defining Layer 3 Switching 11-2
Understanding Packet Flow 11-2
Layer 3 Forwarding 11-6
Layer 2 Bridging 11-6
How MAC Addresses are Learned by the Switch 11-7
System Architecture 11-8
Route Processor 11-9
Routing Protocols 11-10
Layer 2 VLAN and Switching 11-10
Cisco Express Forwarding 11-11
CEF Operation 11-12
Switching Fabric and Arbitration 11-13
Line Card Architecture 11-16
CEFA 11-17
CEFA Search Engine 11-17
Fabric Interface 11-17
Private, Shared, and Dual CAMs 11-18
Comparing Data Plane and Control Plane Traffic 11-20
IP Packet Traffic on the Control Plane 11-20
IPX Packet Traffic on the Control Plane 11-21
Miscellaneous Packet Traffic on the Control Plane 11-21
Troubleshooting Half- or Full-Duplex Negotiation 11-21
Half- and Full-Duplex Troubleshooting Commands 11-22
Troubleshooting IP Layer 3 Connections 11-25
IP Layer 3 Connection Troubleshooting Commands 11-25
Checking the IP Routing Table 11-27
Checking the Interface Status 11-28
Checking the IP CEF Adjacencies 11-30
Checking the Interface CAM Table Entries 11-32
Troubleshooting IPX Layer 3 Routing 11-38
IPX Layer 3 Connection Troubleshooting Commands 11-38
Checking the IPX Routing Table 11-39
Checking the IPX CEF Adjacencies 11-40
Troubleshooting Layer 3 IP Multicast Switching 11-43
Layer 3 IP Multicast Overview 11-43