Dell MX9116n EMC SmartFabric OS10 User Guide Release 10.5.0 - Page 400

Port Auth Status: --more-- UNAUTHORIZED Example (when dot1x is not enabled globally) OS10# show dot1x interface 802.1x not enabled in the system OS10# Supported Releases 10.2.0E or later Far-end failure detection Far-End Failure Detection (FEFD) is a protocol that detects remote data link errors in a network. FEFD uses a link layer echo protocol to detect and signal far-end failures over Ethernet and optical links. When you enable FEFD, switches periodically exchange FEFD echo frames to identify link failures. If the local switch does not receive an echo from its peer for the time interval of three times the configured FEFD message interval, the local switch assumes that the peer link is down. The default interval for FEFD message interval is 15 seconds. For example, with the default configuration, if the local switch does not receive an echo message for 45 seconds from its peer, it brings the peer link down. FEFD helps detect far-end failure when the following problems occur: • Only one side receives packets although the physical layer (L1) of the link is up on both sides. • Transceivers are not connected to the correct ports. FEFD states FEFD comprises the following four states: • Idle-FEFD is disabled. • Unknown-Shown when FEFD is enabled and changes to bi-directional after successful handshake with the peer. Also shown if the peer goes down in normal mode. • bi-directional-Interface is up, connected, and receiving echoes of its neighbor. • err-disabled-Only found when FEFD mode is aggressive and when the interface has not received three echoes of its neighbor. To reset an interface in this state, use the fefd reset command. 400 Layer 2