Topology: RID:
C1 - C2 0.0.0.1 - 0.0.0.2
| / \ | | /\ |
W1 W2 0.0.0.11 0.0.0.22
| |
BGP EIGRP
C1 is always selecting W2 as the border router for every route, even if W2 has not any route learnt:
C1:
i 0.0.0.2 [2] via 172.16.1.6, Ethernet1/2, ASBR, Area 0, SPF 26
i 0.0.0.11 [102] via 172.16.1.6, Ethernet1/2, ASBR, Area 0, SPF 26
i 0.0.0.22 [1] via 172.16.1.6, Ethernet1/2, ASBR, Area 0, SPF 26
Interface PID Area AF Cost State Nbrs F/C
Et1/2 100 0 ipv4 1 P2P 1/1
Et1/1.780 100 0 ipv4 1000 P2P 1/1
Et0/0 100 0 ipv4 10 P2P 1/1
C2:
i 0.0.0.1 [10] via 172.16.1.1, Ethernet0/0, ASBR, Area 0, SPF 27
i 0.0.0.11 [100] via 172.16.1.14, Ethernet1/1, ASBR, Area 0, SPF 27
i 0.0.0.22 [1] via 172.16.1.18, Ethernet1/2.780, ASBR, Area 0, SPF 27
Interface PID Area AF Cost State Nbrs F/C
Et1/2.780 100 0 ipv4 1 P2P 1/1
Et1/1 100 0 ipv4 100 P2P 1/1
Et0/0 100 0 ipv4 10 P2P 1/1
W1:
i 0.0.0.2 [1] via 172.16.1.13, GigabitEthernet2/0, ASBR, Area 0, SPF 21
i 0.0.0.1 [10] via 172.16.1.9, GigabitEthernet0/0.780, ASBR, Area 0, SPF 21
i 0.0.0.22 [2] via 172.16.1.13, GigabitEthernet2/0, ASBR, Area 0, SPF 21
Interface PID Area AF Cost State Nbrs F/C
Gi2/0 100 0 IPv4 1 P2P 1/1
Gi0/0.780 100 0 IPv4 10 P2P 1/1
W2:
i 0.0.0.1 [10] via 172.16.1.5, GigabitEthernet2/0, ASBR, Area 0, SPF 19
i 0.0.0.2 [1] via 172.16.1.17, GigabitEthernet0/0.780, ASBR, Area 0, SPF 19
i 0.0.0.11 [101] via 172.16.1.17, GigabitEthernet0/0.780, ASBR, Area 0, SPF 19
Interface PID Area AF Cost State Nbrs F/C
Gi0/0.780 100 0 IPv4 1 P2P 1/1
Gi2/0 100 0 IPv4 10 P2P 1/1
C1 is the only one not respecting the topology, so when routes are lost from W2, C1 still selects W2 creating a black hole:
Routing entry for 192.168.200.0/24
Known via "ospfv3 100", distance 110, metric 200
Tag 1480, type extern 2, forward metric 102
Last update from 172.16.1.6 on Ethernet1/2, 00:21:34 ago <-- IP of W2
Routing Descriptor Blocks:
* 172.16.1.6, from 0.0.0.11, 00:21:34 ago, via Ethernet1/2 <-- RID is from W1 but IP and IF is towards W2
Route metric is 200, traffic share count is 1
Route tag 1480
