Alcatel-Lucent 6850-48 Network Guide

Configuring BFD

Configuring BFD

page 30-20

OmniSwitch AOS Release 6 Network Configuration Guide

The above command establishes a BFD session on interface named int1 with OSPF DR neighbors in full 
state only. To establish a BFD session on an interface with all neighbors which are greater than or equal to 
“2-way” state, use the 

 command as shown below:

-> ip ospf interface int2 bfd-std all-nbrs

The above command establishes a BFD session on interface named int2 with all OSPF neighbors that are 
greater than or equal to “2-way” state. 

Note. By default, BFD session is enabled on an interface with all neighbors which are greater than or 
equal to “2-way” state.

When any neighbors are added to this interface, OSPF informs BFD about the newly added neighbor(s); 
BFD then establishes a session with them. Use the 

 command to view BFD 

sessions with all BFD neighbors, as shown below:

-> show ip bfd-std sessions

Neighbor    Interface            Local  Remote  Negotiated  Negotiated Echo Rx

IP Address  Address       State  Disc   Disc     Tx          Rx 

-----------+------------+-------+------+------+------------+----------+---------

25.25.25.1   25.25.25.25  UP     45      53     100          100        200

26.26.26.63  26.26.26.36  INIT   43      21     200          200        200

To view a BFD session with a particular neighbor, use the 

command followed by 

the local session discriminator. For example: 

-> show ip bfd-std session 45

Interface address

: 10.172.18.16,

Neighbor address

: 10.172.18.17,

State: UP,

Local discriminator

: 45,

Remote discriminator  : 53,

Protocol: OSPF,

Negotiated Tx interval: 100,

Negotiated Rx interval: 100,

Echo Rx interval

: 200,

Multiplier

: 3,

Tx packet counter

: 4321,

Rx packet counter

: 4675,

Protocol enabled

: OSPF

Whenever there is any change to the interface/neighbor list or interface/neighbor state, OSPF immediately 
informs BFD about the changes. Additionally, whenever BFD detects any changes to the other end, BFD 
updates its database accordingly and informs OSPF for its fastest convergence.