EIGRP - Redistribution - RIP - OSPF

Hi guys, now we are still runing on EIGRP, but what if we have to adapt in different routing Protocol? it's called redistribution. This is the way we have to do, to connecting one routing protocol into different one.

Redistribute Rip into EIGRP
As usual, Configure R1, R2 and R3 as EIGRP. On R1 add ip loopback which will be advertise as RIP, then redistributed it into EIGRP. Check this configuration below :

• R1(Config)#int lo100
• R1(Config-if)#ip address 100.100.100.100 255.255.255.255

Advertise to RIP

• R1(Config)#router rip
• R1(Config-router)#version 2
• R1(Config-router)#no auto-summary
• R1(Config-router)#network 100.100.100.0

Resitribute to EIGRP

• R1(Config)#router eigrp 1
• R1(Config-router)#redistribute rip metric 1 1 1 1 1

What does metric means? Metric value on eigrp is :

• Bandwidth metric in Kbits per second
• EIGRP delay metric, in 10 microsecond units
• EIGRP reliability metric where 255 is 100% reliable
• EIGRP effective bandwidth metric (Loading) where 255 loaded
• EIGRP MTU of the path

Ignore that value, use this value : 

• R1(Config-router)#redistribute rip metric 1 1 1 1 1

In this case, metric value is different with the actual condition. But its function and how this routing works, is not different, cause we are riding from external route. The most important is metric must be filled up, now matter how much the value is, there is no effect.

As shown on R3, there is EX behind network 100.100.100.100. EX means that network 100.100.100.100 comes from external / different routing protocol.

Redistribute OSPF to EIGRP

On R1 add ip loopback which will be advertise as OSPF, then redistributed it into EIGRP. Check this configuration below :

• R1(Config)#int lo101
• R1(Config-if)#ip address 101.101.101.101 255.255.255.255

Advertise to OSPF

• R1(Config)#router OSPF 1
• R1(Config-router)#network 101.101.101.101 0.0.0.0 area 0

Resitribute to EIGRP

• R1(Config)#router eigrp 1
• R1(Config-router)#redistribute ospf 1 metric 1 1 1 1 1

EIGRP - Authentication - Summarization - Unicast Update - Default Route Summary Address

EIGRP - Authentication
In EIGRP, there is only MD5 Authenication, no clear text authentication. So, here are the configuration :

EIGRP - Summarization

Summarization makes several route become only one summary. We have to advertise some ip loopback in R3 then summarized it. As it shown in R1, its already summarized as 10.0.0.0/29.

Add configuration below, in interface fa0/0 R3, but you must calculate its advertise prefix :

• R3(config-id)#ip summary-address eigrp 1 10.0.0.0 255.255.255.248

EIGRP - Unicast Update

By default EIGRP use its multicast 224.0.0.10 to update their routing table. This time we will change to unicast update.

Change to unicast (R1-R2)

• R1(config-router)#neighbour 12.12.12.2 s0/0

Change to unicast (R2-R1)

• R2(config-router)#neighbour 12.12.12.1 s0/0

You could check its update by activate "debug ip packet detail" on each router. Make sure its update already change from 224.0.0.10 to its neighbour.

• R1(config)#debug ip packet detail

EIGRP - Default Route - Summary Address

Default route can be configure and redistributed through EIGRP, so each router no need to configure default route one by one.

Configure text below into interface s0/0 (Configure into interface which define as Router core):

• R1(config-router)#int s0/0
• R1(config-if)#ip summary-address eigrp 1 0.0.0.0 0.0.0.0