Core Issue
Cisco Express Forwarding (CEF) is a Layer 3 (L3) IP switching technology that uses data structures called Forwarding Information Base (FIB) and adjacency tables for expedited packet forwarding. When distributed CEF (dCEF) is enabled, a copy of the FIB and adjacency tables are maintained on the line cards, enabling them to CEF switch packets between port adapters. This offloads the central route processor, resulting in improved performance.
Resolution
To display CEF-related information on all line cards, issue the show cef linecard command from user EXEC or privileged EXEC mode. To view information only on a specific line card, issue the slot-number option.
For additional information, refer to the Verifying Cisco Express Forwarding Status on VIPs and LCs section of Troubleshooting CEF-Related Error Messages.
