EIGRP to EIGRP Route Redistribute

When a router, normally a border router, is running two EIGRP ASs and they need to communicate ,route redistribution is needed. Below is an example:

R2 and R3 have no EIGRP routes for each other , instead R1 the border router knows both routes from each EIGRP AS. I want R2 and R3 to have each other routes so I will configured route redistribution on each AS.

Here I take a look at what routes each router knows


R2#show ip route eigrp 
R2#



R3#show ip route eigrp 
R3#



R1#show ip route eigrp  
     2.0.0.0/32 is subnetted, 1 subnets
D       2.2.2.2 [90/2297856] via 172.12.123.2, 00:00:03, Serial0/0
     3.0.0.0/32 is subnetted, 1 subnets
D       3.3.3.3 [90/2297856] via 172.12.123.3, 00:00:27, Serial0/0


Here I verify the neighbor relationship between the routers



R1#show ip eigrp neighbors 
IP-EIGRP neighbors for process 100
H   Address                 Interface       Hold Uptime   SRTT   RTO  Q  Seq
                                            (sec)         (ms)       Cnt Num
0   172.12.123.2            Se0/0            130 00:05:29    8   200  0  2
IP-EIGRP neighbors for process 50
H   Address                 Interface       Hold Uptime   SRTT   RTO  Q  Seq
                                            (sec)         (ms)       Cnt Num
0   172.12.123.3            Se0/0            133 00:02:39   16   200  0  2




First I configured route redistribution of EIGRP 50 into AS 100, EIGRP requires that each of the 5 metrics to be define.


R1(config)#router eigrp 100
R1(config-router)#redistribute eigrp 50 metric 1500 10 255 1 1500



Taking a look at R2 routing table I can now see the external route learned via EIGRP.


R2#show ip route eigrp 
     3.0.0.0/32 is subnetted, 1 subnets
D EX    3.3.3.3 [170/2221056] via 172.12.123.1, 00:00:39, Serial0/0

I want the redistribution to be two-way so I configure the other side.



R1(config)#router eigrp 50
R1(config-router)#redistribute eigrp 100 metric 1500 10 255 1 1500


R3#show ip route eigrp
     2.0.0.0/32 is subnetted, 1 subnets
D EX    2.2.2.2 [170/2221056] via 172.12.123.1, 00:00:27, Serial0/0