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Bidirectional Forwarding Detection (BFD)
Bidirectional forwarding detection (BFD) is a detection protocol that provides fast forwarding path failure detection.
The Dell Force10 operating software (FTOS) implementation is based on the standards specified in the IETF Draft draft-
ietf-bfd-base-03 and supports BFD on all Layer 3 physical interfaces including virtual local area network (VLAN) 
interfaces, and port-channels.
BFD is supported on the C-Series, E-Series, Z-Series, and S4810 platforms.
bfd all-neighbors
Enable BFD sessions with all neighbors discovered by Layer 3 protocols intermediate system to intermediate system (IS-
IS), open shortest path first (OSPF), or border gateway protocol (BGP) on router interfaces, and (optionally) reconfigure 
the default timer values.
C-Series, E-Series, Z-Series, S4810
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 50 to 1000. The default is 
100.
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 50 to 1000. The default is 100.
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 
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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