Understanding CEF Error Messages
With current-generation Cisco IOS routers and Catalyst switches, some error messages pertaining to CEF are platform specific. As a result, you need to understand platform differences when troubleshooting CEF error messages. Nevertheless, Table 4-5 lists the general CEF EXEC error messages applicable to all Cisco IOS routers and Catalyst switches when configuring CEF and CEF features.
Table 4-5. General CEF EXEC Error Messages
Error Message |
Troubleshooting Action |
Must enable IP routing first. |
When enabling CEF, IP routing must be enabled first. |
Cannot disable CEF on this platform. |
When disabling CEF, some platforms, such as the Catalyst 6500, do not support disabling CEF. |
CEF is not enabled. |
When attempting to configure a global configuration command that requires CEF, CEF must first be enabled. |
CEF not enabled on this interface. Enable first. |
When attempting an interface configuration that requires CEF, CEF must be enabled first. |
A useful tool when working with CEF error messages is the Error Message Decoder on Cisco.com found at the following website (you must be a registered Cisco.com user):