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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 10. Session State Changes
Important Points to Remember
BFD for line card ports is hitless, but is not hitless for VLANs because they are instantiated on the RPM.
The Dell Networking OS supports a maximum of 100 sessions per BFD agent. Each linecard processor has a BFD Agent, so
the limit translates to 100 BFD sessions per linecard.
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 and virtual links.
Protocol Liveness is supported for routing protocols only.
The Dell Networking OS supports only OSPF, OSPFv3, BGP, and VRRP protocols as BFD clients.
Configure BFD
This section contains the following procedures.
Configure BFD for Physical Ports
Configure BFD for Port-Channels
Configure BFD for Static Routes
Configure BFD for OSPF
Configure BFD for OSPFv3
Configure BFD for BGP
Bidirectional Forwarding Detection (BFD)
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