receives a Down status notification from the remote system, the session state on the local system
changes to Init.
Figure 9. 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.
Bidirectional Forwarding Detection (BFD) 147