This is a really simple EIGRP lab, based off of a lab objective I ran into over this past weekend. There are a couple different ways to solve it, but for as simple as the topology is it makes for an interesting lab. As promised, I’ll deliver on my MPLS labs, but I wanted to post this one as it was really quick to set up.
Here’s the scenario, you have three routers, conveniently named R1 R2 and R3. All connected on a shared Ethernet segment. The objective is to have a full mesh peers, but achieve hub-and-spoke routing with R1 as the hub (i.e. R2 and R3 route all traffic through R1). When completed, your results should look similar to the following:
R2#show ip route eigrp
1.0.0.0/32 is subnetted, 1 subnets
D 1.1.1.1 [90/156160] via 10.10.123.1, 00:00:53, FastEthernet0/0
3.0.0.0/32 is subnetted, 1 subnets
D 3.3.3.3 [90/158720] via 10.10.123.1, 00:00:28, FastEthernet0/0
D EX 213.0.0.0/24 [170/2560005376] via 10.10.123.1, 00:05:43, FastEthernet0/0
D EX 212.0.0.0/24 [170/2560005376] via 10.10.123.1, 00:05:43, FastEthernet0/0
D EX 211.0.0.0/24 [170/2560005376] via 10.10.123.1, 00:05:43, FastEthernet0/0
D EX 210.0.0.0/24 [170/2560005376] via 10.10.123.1, 00:05:43, FastEthernet0/0
R2#show ip eigrp neighbors
IP-EIGRP neighbors for process 200
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
1 10.10.123.3 Fa0/0 12 00:05:51 27 200 0 17
0 10.10.123.1 Fa0/0 11 00:07:33 137 822 0 19
R3#show ip route eigrp
1.0.0.0/32 is subnetted, 1 subnets
D 1.1.1.1 [90/156160] via 10.10.123.1, 00:02:40, FastEthernet0/0
2.0.0.0/32 is subnetted, 1 subnets
D 2.2.2.2 [90/158720] via 10.10.123.1, 00:02:01, FastEthernet0/0
D EX 200.0.0.0/24 [170/2560005376] via 10.10.123.1, 00:07:30, FastEthernet0/0
D EX 201.0.0.0/24 [170/2560005376] via 10.10.123.1, 00:07:30, FastEthernet0/0
D EX 202.0.0.0/24 [170/2560005376] via 10.10.123.1, 00:07:30, FastEthernet0/0
D EX 203.0.0.0/24 [170/2560005376] via 10.10.123.1, 00:07:30, FastEthernet0/0
R3#show ip eigrp neighbors
IP-EIGRP neighbors for process 200
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
1 10.10.123.2 Fa0/0 11 00:07:46 186 1116 0 19
0 10.10.123.1 Fa0/0 10 00:07:46 183 1098 0 19
While meeting the following restrictions:
– You may not change the IP Address on any interface.
– You may not create any new interfaces.
– You may not add any route-maps.
– You can not modify the configuration on the switch.
– You can not modify the configuration on the switch.
Diagrams: