Administrator Guide

Session State Changes
The following illustration shows how the session state on a system changes based on the status notification it receives from the
remote system. For example, if a session on a system is down and it receives a Down status notification from the remote
system, the session state on the local system changes to Init.
Figure 11. Session State Changes
Important Points to Remember
● The default BFD transmit or receive interval is 1000 milliseconds for this switch, although the default value is 200
milliseconds for other model switches, as all switches use a common code. Different switches may use different settings for
optimal performance.
● Enable BFD on both ends of a link.
● Demand mode, authentication, and the Echo function are not supported.
● BFD is not supported on multi-hop.
● Protocol Liveness is supported for routing protocols only.
● Dell EMC Networking OS supports static routes, OSPF, OSPFv3, IS-IS, BGP, IPv6 BGP, and VRRP protocols as BFD clients.
NOTE: VRRP for IPv6 is not supported as a BFD client.
● Dell EMC Networking OS supports default and nondefault VRFs for IPv4 and IPv6 BGP.
Configure BFD
This section contains the following procedures.
● Configure BFD for Static Routes
● Configure BFD for OSPF
● Configure BFD for OSPFv3
● Configure BFD for IS-IS
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Bidirectional Forwarding Detection (BFD)