301
Destination: 1.1.1.0/24
Protocol: BGP Process ID: 0
SubProtID: 0x1 Age: 00h03m08s
Cost: 100 Preference: 255
Tag: 0 State: Active Adv
OrigTblID: 0x1 OrigVrf: default-vrf
TableID: 0x2 OrigAs: 0
NBRID: 0x15000000 LastAs: 0
AttrID: 0x0 Neighbor: 2.0.1.1
Flags: 0x10060 OrigNextHop: 2.0.1.1
Label: NULL RealNextHop: 2.0.2.1
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: GigabitEthernet2/0
BkTunnel ID: Invalid BkInterface: N/A
The output shows that Router C communicates with network 1.1.1.0/24 through the path Router
C<—>Router D<—>Router A.
BGP FRR configuration example
Network requirements
As shown in
Figure 71
, configure BGP FRR so that when Link B fails, BGP uses Link A to forward traffic.
Figure 71
Network diagram
Configuration procedure
1.
Configure IP addresses for interfaces. (Details not shown.)
2.
Configure OSPF in AS 200 to ensure connectivity among Router B, Router C, and Router D.
(Details not shown.)
3.
Configure BGP connections:
# Configure Router A to establish EBGP sessions with Router B and Router C, and advertise
network 1.1.1.1/32.
<RouterA> system-view
Router B
Router C
Router D
AS 200
AS 100
Router A
Loop0
1.1.1.1/32
Loo
p0
4.4.4.4/32
GE2/0
30.1.1.1/24
GE1/0
10.1.1.1/24
GE1/0
10.1.1.2/24
GE2/0
20.1.1.2/24
GE2/0
40.1.1.4/24
GE1/0
20.1.1.4/24
GE1/0
30.1.1.3/24
GE2/0
40.1.1.3/24
Link A
Link B
Loop0
2.2.2.2/32
Loop0
3.3.3.3/32