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
• Dell EMC Networking OS supports 128 sessions per stack unit at 300 minimum transmit and receive intervals with a multiplier of 3, 64
sessions at 150 minimum transmit and receive intervals with a multiplier of 3, and 32 sessions at 100 minimum transmit and receive
intervals with a multiplier of 3.
• 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.
• Dell EMC Networking OS supports default and nondefault VRFs for IPv4 and IPv6 BGP.
• Dell EMC Networking OS does not recommend using 50 milliseconds as transmit and receive intervals in a production network.
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
• Configure BFD for BGP
• Configure BFD for VRRP
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Bidirectional Forwarding Detection (BFD)