BFD session is established on two network devices, used to detect the bidirectional forwarding paths between network devices for applications the service. BFD itself does not neighbor discovery mechanism, but to inform their neighbors of information by the upper application services to establish a session. Periodically send BFD packets quickly after the session is established, if not received within the detection time of BFD packets is considered bidirectional forwarding path fails, the service notifies the upper application corresponding treatment. Below OSPF BFD for example, a brief conversation workflow.
SW2的配置
接口配置：
interface Ethernet0/0/1
port link-type access
port default vlan 10
interface Ethernet0/0/2
port link-type access
port default vlan 20
interface Ethernet0/0/3
port link-type trunk
port trunk allow-pass vlan 2 to 4094
interface Ethernet0/0/4
port link-type trunk
port trunk allow-pass vlan 2 to 4094
SW1 configuration
Vlan1 address mark is interlocked with the upper switch
interface Vlanif1
IP address 192.168.1.1 255.255.255.0
Vlanif10 interface
IP address 192.168.10.252 255.255.255.0
vrrp vrid. 1 Virtual-IP 192.168.10.254
vrrp vrid priority. 1 120
vrrp vrid the session. 1 10 Track BFD-reduced 30
// needs to be sent to specify vrrp bfd-session 10 (local identifier )
// configure BFD fast convergence
Peer-ip // end address of own interface and own address
BFD the bind. 1 Use the peer-Vlanif1 Source IP-IP interface 192.168.1.2 192.168.1.1
discriminator 10 // local local identifier
discriminator remote 100 // remote identifier.
the commit
interface Vlanif20
IP address 192.168.20.252 255.255.255.0
VRRP vrid-2 Virtual IP 192.168.20.254
interface MEth0/0/1
interface GigabitEthernet0/0/1
port link-type trunk
port trunk allow-pass vlan 2 to 4094
SW2配置：
interface Vlanif2
ip address 192.168.2.1 255.255.255.0
interface Vlanif10
ip address 192.168.10.253 255.255.255.0
vrrp vrid 1 virtual-ip 192.168.10.254
Vlanif20 interface
IP address 192.168.20.253 255.255.255.0
VRRP vrid-2 Virtual IP 192.168.20.254
VRRP vrid 2 priority 120
VRRP vrid-2 Track bfd the session 20 is reduced 30
VRRP bfd need to transmit local port identifier must be the same
interface MEth0/0/1
interface GigabitEthernet0/0/1
port link-type trunk
port trunk allow-pass vlan 2 to 4094
interface GigabitEthernet0/0/2
port link-type access
port default vlan 2
IP address int Peer-ip // peer vlan2 // own interface address and IP address
BFD 2 the bind-Use the peer IP interface Vlanif2 192.168.2.2 192.168.2.1 Source IP-
discriminator 20 is local // The local discriminator
discriminator remote 101 / / terminal identifier pair
Commit
AR1配置：
interface GigabitEthernet0/0/0
ip address 192.168.1.2 255.255.255.0
interface GigabitEthernet0/0/1
ip address 192.168.2.2 255.255.255.0
Bidirectional Forwarding Detection BFD peer-ip // IP address of the terminal int G0 / 0/0 // IP address of own interface
bfd 1 bind peer-ip 192.168.1.1 interface GigabitEthernet0 / 0/0 source-ip 192.168.1.2
as bis point two-way, so the local BFD peer identifier is an identifier for the peer client identifier are the BFD peer identifier
discriminator local 100 // the local discriminator
discriminator remote 10 // peer identifier
commit
Bidirectional Forwarding Detection the BFD
BFD 2 the bind-Use the peer IP interface 192.168.2.1 the GigabitEthernet0 / 0 /. 1 Source IP 192.168.2.1-
discriminator 101 // local local identifier
discriminator remote 20 // peer identifier
commit