This chapter provides information and commands concerning the following topics:
- Configuring Cisco Express Forwarding
- - Verifying CEF
- - Troubleshooting CEF
- Configuring MPLS on a Frame Mode interface
- Configuring MTU size in label switching
Configuring Cisco Express Forwarding
To enable MPLS, you must first enable Cisco Express Forwarding (CEF) switching.
Router(config)#ip cef |
Enables standard CEF |
Router(config)#ip cef distributed |
Enables dCEF |
Router(config)#no ip cef |
Disables CEF globally |
Router(config)#interface fastethernet 0/1 |
Moves to interface configuration mode |
Router(config-if)#ip route-cache cef |
Enables CEF on the interface |
Verifying CEF
Router#show ip cef |
Displays entries in the forwarding information base (FIB) |
Router#show ip cef summary |
Displays a summary of the FIB |
Router#show ip cef unresolved |
Displays unresolved FIB entries |
Router#show ip cef fastethernet 0/1 |
Displays the FIB entry for the specified interface |
Router#show ip cef fastethernet 0/1 detail |
Displays detailed information about the FIB for the interface |
Router#show cef drop |
Displays packets that are dropped due to adjacencies that are incomplete or nonexistent |
Troubleshooting CEF
Router#debug ip cef |
Displays debug information for CEF |
Router#debug ip cef drop |
Displays debug information about dropped packets |
Router#debug ip cef access-list x |
Displays information from specified access lists |
Router#debug ip cef receive |
Displays information about packets received by IP CEF |
Router#debug ip cef events |
Displays general CEF events |
Router#debug ip cef prefix-ipc |
Displays updates related to IP prefix information |
Router#debug ip cef table |
Produces a table showing events related to the FIB table |