Administrator Guide

4. If the FEFD enabled system is configured to use FEFD in Normal mode and neighboring echoes are not received after three intervals,
the state changes to unknown. You can set each interval from 3 to 255 seconds.
5. If the FEFD system has been set to Aggressive mode and neighboring echoes are not received after three intervals, the state changes
to Err-disabled. You must manually reset all interfaces in the Err-disabled state using the fefd reset [interface] command in
EXEC privilege mode (it can be done globally or one interface at a time) before the FEFD enabled system can become operational
again.
Table 48. State Change When Configuring FEFD
Local Event Mode Local State Remote State Local Admin
Status
Local
Protocol
Status
Remote
Admin Status
Remote
Protocol
Status
Shutdown Normal Admin
Shutdown
Unknown Down Down Up Down
Shutdown Aggressive Admin
Shutdown
Unknown Up Down Up Down
FEFD enable Normal Bi-directional Bi-directional Up Up Up Up
FEFD enable Aggressive Bi-directional Bi-directional Up Up Up Up
FEFD + FEFD
disable
Normal Locally disabled Unknown Up Down Up Down
FEFD + FEFD
disable
Aggressive Locally disabled Err-disabled Up Up Up Down
Link Failure Normal Unknown Unknown Up Down Up Down
Link Failure Aggressive Unknown Unknown Up Down Up Down
Important Points to Remember
• FEFD is supported only on physical Ethernet interfaces, except the management interface.
• FEFD is not supported on copper Ethernet and Fibre Channel ports. FEFD is supported only on fiber Ethernet ports.
• FEFD is not supported on port extender (PE) ports.
• FEFD is not supported on port-channels or port-channel members.
• You can enable FEFD globally or on a per-interface basis. Interface FEFD configurations override global FEFD configurations.
Configuring FEFD
You can configure FEFD on all interfaces from CONFIGURATION mode or on individual interfaces from INTERFACE mode.
To enable FEFD globally on all interfaces, use the following command.
• CONFIGURATION mode
fefd-global
To report interval frequency and mode adjustments, use the following commands.
1. Configure two or more connected interfaces for Layer 2 or Layer 3 traffic.
INTERFACE mode
switchport
ip address ip address
2. Activate the ports.
INTEFACE mode
no shutdown
3. Enable FEFD globally on the switch.
CONFIGURATION mode
fefd-global {interval | mode}
Layer 2
515