HP 6125XLG - Configuring BFD for RIP (Single Hop Echo Detection for a Specific Destination)

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<SwitchA> display ip routing-table 120.1.1.0 24 verbose
Summary Count : 1
Destination: 120.1.1.0/24
Protocol: RIP Process ID: 2
SubProtID: 0x1 Age: 04h20m37s
Cost: 1 Preference: 100
Tag: 0 State: Active Adv
OrigTblID: 0x0 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NBRID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 192.168.2.2
Flags: 0x1008c OrigNextHop: 192.168.2.2
Label: NULL RealNextHop: 192.168.2.2
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: Vlan-interface200
BkTunnel ID: Invalid BkInterface: N/A
The output shows that Switch A communicates with Switch C through VLAN-interface 200.
Configuring BFD for RIP (single hop echo detection for a
specific destination)
Network requirements
As shown in Figure 12, VLAN-interface 100 of Switch A and Switch B runs RIP process 1. VLAN-interface
200 of Switch B and Switch C runs RIP process 1.
Configure a static route destined for 100.1.1.0/24 and enable static route redistribution into RIP on both
Switch A and Switch C so Switch B can learn two routes destined for 100.1.1.0/24 through
VLAN-interface 100 and VLAN-interface 200. The route redistributed from Switch A has a smaller cost
than that redistributed from Switch C, so Switch B uses the route through VLAN-interface 200.
Enable BFD for RIP on VLAN-interface 100 of Switch A, and specify VLAN-interface 100 of Switch B as
the destination. When a unidirectional link occurs (packets from Switch A can reach Switch B, but
packets from Switch B cannot reach Switch A), BFD can quickly detect the link failure and notify RIP.
Switch B then deletes the neighbor relationship and the route information learned on VLAN-interface 100,
and does not receive or send any packets from VLAN-interface 100. When the route learned from Switch
A ages out, Switch B uses the route destined for 100.1.1.1 24 through VLAN-interface 200.