CLI Guide

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 Refer to Parameters.
Command Modes
ROUTER OSPF
ROUTER OSPFv3
ROUTER BGP
ROUTER ISIS
INTERFACE (BFD for VRRP only)
Supported Modes Full–Switch
Command History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage Information
All neighbors inherit the timer values congured with the bfd neighbor command except in the following cases:
Timer values congured with the isis bfd all-neighbors commands in INTERFACE mode override
timer values congured with the
bfd neighbor command. Likewise, using the no bfd neighbor
command does not disable BFD on an interface if you explicitly enable BFD using the isis bfd all-
neighbors command.
Neighbors that have been explicitly enabled or disabled for a BFD session with the bfd neighbor or
neighbor bfd disable commands in ROUTER BGP mode do not inherit the global BFD enable/disable
values congured with the bfd neighbor command or congured for the peer group to which a neighbor
belongs. The neighbors inherit only the global timer values (congured with the bfd neighbor command).
Related Commands
show bfd neighbors — displays BFD neighbor information on all interfaces or a specied interface.
bfd neighbor — explicitly enables a BFD session with a BGP neighbor or a BGP peer group.
neighbor bfd disable — explicitly disables a BFD session with a BGP neighbor or a BGP peer group.
bfd disable
Disable BFD on an interface.
Syntax
bfd disable
Re-enable BFD using the no bfd disable command.
Defaults BFD is disabled by default.
Command Modes INTERFACE VRRP
Bidirectional Forwarding Detection (BFD) 273