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Bidirectional Forwarding Detection (BFD) Configuration Module

This configuration module configures the basic BFD (RFC5880) parameters. To configure fast failover with BFD, use the routing protocol configuration modules. At the moment you can use BFD with IS-IS and OSPF.

BFD is supported on these platforms:

Operating system Configurable
timers
OSPF IS-IS
Arista EOS
Aruba AOS-CX
Cisco IOS
Cisco IOS XE
Cisco Nexus OS
Dell OS10
Juniper vMX
Juniper vPTX
Juniper vSRX 3.0
Mikrotik RouterOS 6
Mikrotik RouterOS 7
Nokia SR Linux
Nokia SR OS
VyOS ✅❗

Notes:

  • Junos configuration template configures BFD timers within routing protocol configuration, not in individual interfaces

  • VyOS configuration template configures BFD timers only at global level

Parameters

The following parameters can be set globally or per node/link:

  • min_tx: The desired minimal interval for sending BFD packets, in msec.

  • min_rx: The required minimal interval for receiving BFD packets, in msec

  • min_echo_rx: Echo function timer, in msec

  • multiplier: Number of missed packets before the session is considered down

Global defaults are set pretty high to accommodate a wide range of virtual network devices with varying quality of BFD implementation:

  • min_tx: 1 second (1000 msec)

  • min_rx: 1 second (1000 msec)

  • min_echo_rx: disabled (set to zero)

  • multiplier: 3

Valid intervals and ranges are platform-dependent. Some platforms have lower default values:

platform min-tx min-rx
nxos 1000 msec 500 msec
srlinux 100 msec 100 msec
sros 100 msec 100 msec

Example

To enable BFD using default values on all IS-IS interfaces:

module: [ isis, bfd ]

isis:
 bfd:
  ipv4: True
  ipv6: True