- lastproofread
2023-01-27
BFD (Bidirectional Forwarding Detection)
is described and extended by the following RFCs: 5880
, 5881
and 5883
.
In the age of very fast networks, a second of unreachability may equal millions of lost packets. The idea behind BFD is to detect very quickly when a peer is down and take action extremely fast.
BFD sends lots of small UDP packets very quickly to ensures that the peer is still alive.
This allows avoiding the timers defined in BGP and OSPF protocol to expires.
set protocols bfd peer <address>
Set BFD peer IPv4 address or IPv6 address
set protocols bfd peer <address> echo-mode
Enables the echo transmission mode
set protocols bfd peer <address> multihop
Allow this BFD peer to not be directly connected
set protocols bfd peer <address> source [address <address> | interface <interface>]
Bind listener to specific interface/address, mandatory for IPv6
set protocols bfd peer <address> interval echo-interval <10-60000>
The minimal echo receive transmission interval that this system is capable of handling
set protocols bfd peer <address> interval multiplier <2-255>
Remote transmission interval will be multiplied by this value
set protocols bfd peer <address> interval [receive | transmit] <10-60000>
Interval in milliseconds
set protocols bfd peer <address> shutdown
Disable a BFD peer
set protocols bgp <asn> neighbor <address> bfd
Enable BFD on a single BGP neighbor
set protocols bgp <asn> peer-group <group> bfd
Enable BFD on a BGP peer group
set interfaces ethernet <interface> ip ospf bfd
Enable BFD for OSPF on an interface
set interfaces ethernet <interface> ipv6 ospfv3 bfd
Enable BFD for OSPFv3 on an interface
set protocols isis <name> interface <interface> bfd
Enable BFD for ISIS on an interface
show protocols bfd peer
Show all BFD peers
BFD Peers:
peer 198.51.100.33 vrf default interface eth4.100
ID: 4182341893
Remote ID: 12678929647
Status: up
Uptime: 1 month(s), 16 hour(s), 29 minute(s), 38 second(s)
Diagnostics: ok
Remote diagnostics: ok
Local timers:
Receive interval: 300ms
Transmission interval: 300ms
Echo transmission interval: 50ms
Remote timers:
Receive interval: 300ms
Transmission interval: 300ms
Echo transmission interval: 0ms
peer 198.51.100.55 vrf default interface eth4.101
ID: 4618932327
Remote ID: 3312345688
Status: up
Uptime: 20 hour(s), 16 minute(s), 19 second(s)
Diagnostics: ok
Remote diagnostics: ok
Local timers:
Receive interval: 300ms
Transmission interval: 300ms
Echo transmission interval: 50ms
Remote timers:
Receive interval: 300ms
Transmission interval: 300ms
Echo transmission interval: 0ms