Configure the IP routing as in Figure 3-13 as directed. Section 2.1: EIGRP (7 Points)
You should configure EIGRP AS1 on R1-R2-R3. You could just enable EIGRP with a network 10.0.0.0 statement everywhere. But as you can see in Figure 3-13, R1 does not have all its network 10 interfaces included in EIGRP. You will need to configure an inverse mask for the networks you require advertised and included in EIGRP on R1; preferably, configure R2 and R3 in the same manner although you will not loose marks for this in this case. Do not forget to disable auto summarization on all your routers as a matter of good practice even though strictly speaking this is not required on R3. If you have configured this correctly as shown in Example 3-11 through Example 3-13, you have scored 2 points. Example 3-11. R1 Initial EIGRP Configurationrouter eigrp 1 network 10.1.1.0 0.0.0.15 network 10.90.90.0 0.0.0.15 no auto-summary Example 3-12. R2 Initial EIGRP Configurationrouter eigrp 1 network 10.2.2.0 0.0.0.15 network 10.90.90.0 0.0.0.15 network 172.16.0.0 no auto-summary Example 3-13. R3 Initial EIGRP Configurationrouter eigrp 1 network 10.3.3.0 0.0.0.15 network 172.16.0.0 no auto-summary
As in Lab 2, a question, which will eat into your time, that is also in preparation for a task within the IOS section. To authenticate the EIGRP updates, you need to configure a key chain with appropriate key-string and enable it on the EIGRP interfaces (with exception to the loopbacks). If you configured this correctly as shown in Example 3-14 through Example 3-15, you have scored 2 points. Example 3-14. R1 Initial EIGRP Authentication Configurationkey chain Brussels key 1 key-string Asterix ! interface Serial0/0 ip authentication mode eigrp 1 md5 ip authentication key-chain eigrp 1 Brussels Example 3-15. R2 Initial EIGRP Authentication Configurationkey chain Brussels key 1 key-string Asterix ! interface FastEthernet0/0 ip authentication mode eigrp 1 md5 ip authentication key-chain eigrp 1 Brussels ! interface Serial0/0 ip authentication mode eigrp 1 md5 ip authentication key-chain eigrp 1 Brussels Example 3-16. R3 Initial EIGRP Authentication Configurationkey chain Brussels key 1 key-string Asterix ! interface FastEthernet0/0 ip authentication mode eigrp 1 md5 ip authentication key-chain eigrp 1 Brussels
Versions of Cisco IOS Software prior to Release 12.2.16 had a neighbor command within EIGRP. Subsequent releases do not. Even though you are running authentication, further EIGRP speakers could be added to VLAN1 and configured with the correct authentication; if this happened, R3 would be able to receive routes from them. R3 can selectively receive routes by configuring a distribute-list with the gateway option enabled; this should contain purely R2's Ethernet address within a prefix-list. If you have configured this correctly as shown in Example 3-17, you have scored 3 points. Example 3-17. R3 EIGRP Gateway Configurationrouter eigrp 1 distribute-list gateway neighbor-R2 in FastEthernet 0/0 ! ip prefix-list neighbor-R2 seq 5 permit 172.16.0.1/32 Section 2.2: OSPF (5 Points)
You will need to configure OSPF on R1, R2, R4, R5, R6, R7, and R8 ensuring that all OSPF-only routers have their loopback interfaces advertised within their Ethernet assigned areas. This means network 10.1.1.0/28 will be advertised within both EIGRP and OSPF. You will also need to configure a virtual link between R6 and R5 to extend area 0 out to R5 area 5 via area 4. You can manually configure your router ID within OSPF if you choose to even though it will not change within the lab. If you have configured this correctly as shown in Example 3-18 through Example 3-24, then you have scored 2 points. Example 3-18. R1 Initial OSPF Configurationrouter ospf 30 network 10.1.1.0 0.0.0.15 area 0 network 10.10.10.0 0.0.0.15 area 0 network 10.100.100.0 0.0.0.15 area 0 network 10.80.80.0 0.0.0.255 area 2 network 10.90.90.0 0.0.0.15 area 0 Example 3-19. R2 Initial OSPF Configurationrouter ospf 1 network 10.90.90.0 0.0.0.15 area 0 Example 3-20. R4 Initial OSPF Configurationrouter ospf 1 network 10.4.4.0 0.0.0.15 area 1 network 10.10.10.0 0.0.0.15 area 0 network 10.40.40.0 0.0.0.15 area 1 network 10.100.100.0 0.0.0.15 area 0 Example 3-21. R5 OSPF Configurationrouter ospf 1 router-id 10.5.5.5 area 4 virtual-link 10.6.6.6 network 10.5.5.0 0.0.0.15 area 5 network 10.50.50.0 0.0.0.7 area 5 network 10.99.99.0 0.0.0.7 area 4 Example 3-22. R6 Initial OSPF Configurationrouter ospf 1 router-id 10.6.6.6 area 4 virtual-link 10.5.5.5 network 10.6.6.0 0.0.0.15 area 6 network 10.60.60.0 0.0.0.7 area 6 network 10.80.80.0 0.0.0.255 area 2 network 10.99.99.0 0.0.0.7 area 4 network 10.100.100.0 0.0.0.15 area 0 NOTE R6 loopback network 10.6.6.0/28 can be advertised within either area 2 or 6 because R6 has two Ethernet interfaces, one of which is in area 2 and the other in area 6. Example 3-23. R7 OSPF Configurationrouter ospf 1 network 10.7.7.0 0.0.0.15 area 6 network 10.60.60.0 0.0.0.7 area 6 Example 3-24. R8 OSPF Configurationrouter ospf 1 network 10.8.8.0 0.0.0.15 area 2 network 10.80.80.0 0.0.0.255 area 2
The Frame Relay network is NBMA; without using the network command and without having broadcast capability within your Frame Relay maps, you will need to statically configure neighbors. You will need to configure neighbor 10.100.100.1 and neighbor 10.100.100.2 under the OSPF process on R4; you could also configure R1 and R6 with neighbor statements pointing to R4 but this could be considered overconfiguration as it is not strictly required to ensure operability. This particular Frame Relay scenario will also introduce a DR (Designated Router), which should be R4 as it is the hub; in fact, because the Router ID being highest, R6 would become the DR if permitted to. The simplest method of ensuring R4 becomes the DR is by not allowing R1 and R6 to enter into the DR negotiations by configuring ip ospf priority 0 under the Frame Relay interfaces of R1 and R6. If you have configured these items correctly as shown in Example 3-25 through Example 3-27, you have scored 2 points. NOTE Example 3-25 through Example 3-27 also show the required configuration for the MTU issue, which has previously been discussed in the initial Frame Relay section of the de-brief. Without configuring the command ip ospf mtu-ignore under the physical Frame Relay interfaces on R1 and R6, you will find that your OSPF network will fail over the Frame Relay. Example 3-25. R1 OSPF Frame Relay and Neighbor Configurationinterface Serial0/1 ip mtu 950 encapsulation frame-relay ip ospf priority 0 ip ospf mtu-ignore Example 3-26. R4 OSPF Neighbor Configurationrouter ospf 1 neighbor 10.100.100.1 neighbor 10.100.100.2 Example 3-27. R6 OSPF Frame Relay and Neighbor Configurationinterface Serial5/0 ip mtu 950 encapsulation frame-relay ip ospf priority 0 ip ospf mtu-ignore
You will need to configure your loopback interfaces on R1, R4, R5, R6, R7, and R8, which are advertised within OSPF with ip ospf-network point-to-point statements to ensure they are advertised with the correct mask as opposed to /32 host routes to your network. You will also need to configure your virtual-template interfaces on R5 and R6 with the command no peer neighbor-route to remove the /32 host routes that are added to the routing table when the PPP links become active over the ATM and on the serial interface connection between R1 and R2. If you have configured this correctly, you have scored 1 point. Section 2.3: Redistribution (4 Points)
You are not being requested to perform mutual redistribution here so you are required to redistribute OSPF into EIGRP on R2. To allow only OSPF routes with masks greater than /16, you need to configure a route map and prefix-list accordingly along with a default metric. You should realize that the majority of your OSPF network will not have visibility of VLAN1 172.16.0.0/16 and R2 loopback0 10.2.2.0/28 as EIGRP has not been redistributed into OSPF. The lab guidelines do state that these networks are exempt from the full IP visibility required between routers and this will become apparent in the BGP section. If you have configured this correctly as shown in Example 3-28, you have scored 4 points. Example 3-28. R2 OSPF Redistribution Configurationrouter eigrp 1 redistribute ospf 1 route-map eigrp-ospf default-metric 1000 10 255 1 1500 ! ! ip prefix-list /16 seq 5 permit 0.0.0.0/0 ge 16 ! route-map eigrp-ospf permit 10 match ip address prefix-list /16 |