December 17, 2013

Lab 08: BGP Confederation

Let's configure BGP confederation. R1 is connected to Sub-AS 1002 and AS 3000:

R1#show running-config | section bgp
router bgp 1001
 no synchronization
 bgp router-id 1.1.1.1
 bgp log-neighbor-changes
 bgp confederation identifier 2000
 bgp confederation peers 1002
 neighbor 2.2.2.2 remote-as 1001
 neighbor 2.2.2.2 update-source Loopback0
 neighbor 2.2.2.2 route-reflector-client
 neighbor 3.3.3.3 remote-as 1001
 neighbor 3.3.3.3 update-source Loopback0
 neighbor 3.3.3.3 route-reflector-client
 neighbor 4.4.4.4 remote-as 1002
 neighbor 4.4.4.4 ebgp-multihop 2
 neighbor 4.4.4.4 update-source Loopback0
 neighbor 5.5.5.5 remote-as 3000
 neighbor 5.5.5.5 ebgp-multihop 2
 neighbor 5.5.5.5 update-source Loopback0
 no auto-summary

As you see, AS 1002 is configured as confederation peer. Confederation identifier is 2000 and this is configured on all routers in Sub-AS 1001.

R2#show running-config | section bgp
router bgp 1001
 no synchronization
 bgp router-id 2.2.2.2
 bgp log-neighbor-changes
 bgp confederation identifier 2000
 network 20.0.0.1 mask 255.255.255.255
 neighbor 1.1.1.1 remote-as 1001
 neighbor 1.1.1.1 update-source Loopback0
 no auto-summary


R3#show running-config | section bgp
router bgp 1001
 no synchronization
 bgp router-id 3.3.3.3
 bgp log-neighbor-changes
 bgp confederation identifier 2000
 network 30.0.0.1 mask 255.255.255.255
 neighbor 1.1.1.1 remote-as 1001
 neighbor 1.1.1.1 update-source Loopback0
 no auto-summary

As a result, Loopback 1 addresses are observed on all routers. This is R1's routing table:

R1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

     1.0.0.0/32 is subnetted, 1 subnets
C       1.1.1.1 is directly connected, Loopback0
     50.0.0.0/32 is subnetted, 1 subnets
B       50.0.0.1 [20/0] via 5.5.5.5, 00:07:40
     2.0.0.0/32 is subnetted, 1 subnets
O       2.2.2.2 [110/11] via 12.0.0.2, 00:20:31, Ethernet2/0
     3.0.0.0/32 is subnetted, 1 subnets
O       3.3.3.3 [110/11] via 13.0.0.2, 00:20:31, Ethernet2/1
     4.0.0.0/32 is subnetted, 1 subnets
O       4.4.4.4 [110/65] via 14.0.0.2, 00:20:31, Serial0/0
     20.0.0.0/32 is subnetted, 1 subnets
B       20.0.0.1 [200/0] via 2.2.2.2, 00:26:20
     5.0.0.0/32 is subnetted, 1 subnets
O       5.5.5.5 [110/65] via 15.0.0.2, 00:20:33, Serial0/1
     40.0.0.0/32 is subnetted, 1 subnets
B       40.0.0.1 [200/0] via 4.4.4.4, 00:20:33
     12.0.0.0/30 is subnetted, 1 subnets
C       12.0.0.0 is directly connected, Ethernet2/0
     13.0.0.0/30 is subnetted, 1 subnets
C       13.0.0.0 is directly connected, Ethernet2/1
     14.0.0.0/30 is subnetted, 1 subnets
C       14.0.0.0 is directly connected, Serial0/0
     30.0.0.0/32 is subnetted, 1 subnets
B       30.0.0.1 [200/0] via 3.3.3.3, 00:26:20
     15.0.0.0/30 is subnetted, 1 subnets
C       15.0.0.0 is directly connected, Serial0/1

This is R4's routing table:

R4#show ip rou
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

     1.0.0.0/32 is subnetted, 1 subnets
O       1.1.1.1 [110/65] via 14.0.0.1, 00:23:32, Serial0/0
     50.0.0.0/32 is subnetted, 1 subnets
B       50.0.0.1 [200/0] via 5.5.5.5, 00:10:40
     2.0.0.0/32 is subnetted, 1 subnets
O       2.2.2.2 [110/75] via 14.0.0.1, 00:23:32, Serial0/0
     3.0.0.0/32 is subnetted, 1 subnets
O       3.3.3.3 [110/75] via 14.0.0.1, 00:23:32, Serial0/0
     4.0.0.0/32 is subnetted, 1 subnets
C       4.4.4.4 is directly connected, Loopback0
     20.0.0.0/32 is subnetted, 1 subnets
B       20.0.0.1 [200/0] via 2.2.2.2, 00:29:20
     5.0.0.0/32 is subnetted, 1 subnets
O       5.5.5.5 [110/129] via 14.0.0.1, 00:23:33, Serial0/0
     40.0.0.0/32 is subnetted, 1 subnets
C       40.0.0.1 is directly connected, Loopback1
     12.0.0.0/30 is subnetted, 1 subnets
O       12.0.0.0 [110/74] via 14.0.0.1, 00:23:34, Serial0/0
     13.0.0.0/30 is subnetted, 1 subnets
O       13.0.0.0 [110/74] via 14.0.0.1, 00:23:34, Serial0/0
     14.0.0.0/30 is subnetted, 1 subnets
C       14.0.0.0 is directly connected, Serial0/0
     30.0.0.0/32 is subnetted, 1 subnets
B       30.0.0.1 [200/0] via 3.3.3.3, 00:29:21
     15.0.0.0/30 is subnetted, 1 subnets
O       15.0.0.0 [110/128] via 14.0.0.1, 00:23:33, Serial0/0

This is R5's routing table:

R5#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

     1.0.0.0/32 is subnetted, 1 subnets
O       1.1.1.1 [110/65] via 15.0.0.1, 00:25:09, Serial0/1
     50.0.0.0/32 is subnetted, 1 subnets
C       50.0.0.1 is directly connected, Loopback1
     2.0.0.0/32 is subnetted, 1 subnets
O       2.2.2.2 [110/75] via 15.0.0.1, 00:25:09, Serial0/1
     3.0.0.0/32 is subnetted, 1 subnets
O       3.3.3.3 [110/75] via 15.0.0.1, 00:25:09, Serial0/1
     4.0.0.0/32 is subnetted, 1 subnets
O       4.4.4.4 [110/129] via 15.0.0.1, 00:25:09, Serial0/1
     20.0.0.0/32 is subnetted, 1 subnets
B       20.0.0.1 [20/0] via 1.1.1.1, 00:13:05
     5.0.0.0/32 is subnetted, 1 subnets
C       5.5.5.5 is directly connected, Loopback0
     40.0.0.0/32 is subnetted, 1 subnets
B       40.0.0.1 [20/0] via 1.1.1.1, 00:13:06
     12.0.0.0/30 is subnetted, 1 subnets
O       12.0.0.0 [110/74] via 15.0.0.1, 00:25:11, Serial0/1
     13.0.0.0/30 is subnetted, 1 subnets
O       13.0.0.0 [110/74] via 15.0.0.1, 00:25:11, Serial0/1
     14.0.0.0/30 is subnetted, 1 subnets
O       14.0.0.0 [110/128] via 15.0.0.1, 00:25:11, Serial0/1
     30.0.0.0/32 is subnetted, 1 subnets
B       30.0.0.1 [20/0] via 1.1.1.1, 00:13:06
     15.0.0.0/30 is subnetted, 1 subnets
C       15.0.0.0 is directly connected, Serial0/1

# DOWNLOAD LAB 08 GNS3 FILE