Users Guide

Bidirectional Forwarding Detection (BFD)
Bidirectional forwarding detection (BFD) is a detection protocol that provides fast forwarding path failure detection.
The Dell Networking OS implementation is based on the standards specied in the IETF Draft draft-ietf-bfd-base-03, and supports BFD on
all Layer 3 physical interfaces including VLAN interfaces and port-channels
Topics:
• bfd all-neighbors
• ip route bfd
• neighbor bfd
• neighbor bfd disable
• show bfd neighbors
bfd all-neighbors
Enable BFD sessions with all neighbors discovered by Layer 3 protocols virtual router redundancy protocol (VRRP), intermediate system to
intermediate system (IS-IS), open shortest path rst (OSPF), OSPFv3, or border gateway protocol (BGP) on router interfaces, and
(optionally) recongure the default timer values.
Syntax
bfd all-neighbors [interval interval min_rx min_rx multiplier value role
{active | passive}]
Parameters
interval milliseconds (OPTIONAL) Enter the keyword interval to specify non-default BFD session
parameters beginning with the transmission interval. The range is from 50 to 1000. The
default is 200.
min_rx milliseconds Enter the keyword min_rx to specify the minimum rate at which the local system would
like to receive control packets from the remote system. The range is from 50 to 1000. The
default is 200.
multiplier value Enter the keyword multiplier to specify the number of packets that must be missed
in order to declare a session down. The range is from 3 to 50. The default is 3.
role [active |
passive]
Enter the role that the local system assumes:
• Active — The active system initiates the BFD session. Both systems can be active
for the same session.
• Passive — The passive system does not initiate a session. It only responds to a
request for session initialization from the active system.
The default is active.
Defaults See Parameters.
Command Modes
ROUTER OSPF
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