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Dynamic Routing Protocols Lab

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Dynamic routing protocols

Routing Protocol Updates

  1. Enter the commands below on each router to provision a basic RIPv1 configuration and enable RIP on every interface.
router rip
network 10.0.0.0
no auto-summary
  1. Debug the routing protocol updates on R1 with the ‘debug ip rip’ command. Observe the updates being sent and received. What kind of traffic is used (unicast, broadcast or multicast)?
RIP: sending  v1 update to 255.255.255.255 via FastEthernet1/1 (10.0.3.1)
RIP: build update entries
      network 10.0.0.0 metric 1
      network 10.0.1.0 metric 1
      network 10.0.2.0 metric 1
      network 10.1.0.0 metric 2

`255.255.255.255` is the broadcast address.

3) Enter the commands below to enable RIPv2 on every router.

router rip
version 2
  1. What kind of traffic is used for the updates now?
RIP: sending  v2 update to 224.0.0.9 via FastEthernet1/0 (10.0.2.1)
RIP: build update entries
      10.0.0.0/24 via 0.0.0.0, metric 1, tag 0
      10.0.1.0/24 via 0.0.0.0, metric 1, tag 0
      10.0.3.0/24 via 0.0.0.0, metric 1, tag 0
      10.1.0.0/24 via 0.0.0.0, metric 2, tag 0
      10.1.1.0/24 via 0.0.0.0, metric 3, tag 0
      10.1.2.0/24 via 0.0.0.0, metric 3, tag 0
      10.1.3.0/24 via 0.0.0.0, metric 2, tag 0

Sending data to 224.0.0.9. This is Class D IP, used for multicast

  1. Turn off all debugging on R1. no debug ip rip

  2. Check that RIP routes have been added to R1 and it has a route to every subnet in the lab.

R1# show ip route

     10.0.0.0/8 is variably subnetted, 12 subnets, 2 masks
C       10.0.0.0/24 is directly connected, FastEthernet0/0
L       10.0.0.1/32 is directly connected, FastEthernet0/0
C       10.0.1.0/24 is directly connected, FastEthernet0/1
L       10.0.1.1/32 is directly connected, FastEthernet0/1
C       10.0.2.0/24 is directly connected, FastEthernet1/0
L       10.0.2.1/32 is directly connected, FastEthernet1/0
C       10.0.3.0/24 is directly connected, FastEthernet1/1
L       10.0.3.1/32 is directly connected, FastEthernet1/1
R       10.1.0.0/24 [120/1] via 10.0.0.2, 00:00:02, FastEthernet0/0
R       10.1.1.0/24 [120/2] via 10.0.0.2, 00:00:02, FastEthernet0/0
                    [120/2] via 10.0.3.2, 00:00:12, FastEthernet1/1
  1. Why are there two routes to the 10.1.1.0/24 network in the routing table? Because the 10.1.1.0 network is two hops away, either via R5>R4 or via R2>R3

Comparing Routing Protocols

  1. View the RIP database on R1. R1# show ip rip database
  2. Enter the commands below on each router to provision a basic OSPF configuration and enable OSPF on every interface.
router ospf 1
network 10.0.0.0 0.255.255.255 area 0

  1. Give OSPF time to converge. Are RIP routes included in the routing table on R1 now? Why or why not? They will not be, since OSPF has a lower Administrative Distances than RIP

  2. Why is there now only one route to the 10.1.1.0/24 network?

R1#show run | section interface
interface FastEthernet0/0
 ip address 10.0.0.1 255.255.255.0
 duplex auto
 speed auto
interface FastEthernet0/1
 ip address 10.0.1.1 255.255.255.0
 duplex auto
 speed auto
interface FastEthernet1/0
 ip address 10.0.2.1 255.255.255.0
 duplex auto
 speed auto
interface FastEthernet1/1
 bandwidth 10000
 ip address 10.0.3.1 255.255.255.0
 duplex auto
 speed auto
interface Vlan1
 no ip address
 shutdown

the bandiwth on all interfaces is set to auto (and thus 100 Mbps), except for FA1/1, set to bandwitdh 10000 which is 10 Mbps

  1. Disable interface FastEthernet 0/0 on R2. What do you expect to happen to R1’s routing table?

With the interface down, I expect R1 to reconverge via the slower link on FA1/1

  1. Verify your expected changes to R1’s routing table.
R1# show ip route

     10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
C       10.0.1.0/24 is directly connected, FastEthernet0/1
L       10.0.1.1/32 is directly connected, FastEthernet0/1
C       10.0.2.0/24 is directly connected, FastEthernet1/0
L       10.0.2.1/32 is directly connected, FastEthernet1/0
C       10.0.3.0/24 is directly connected, FastEthernet1/1
L       10.0.3.1/32 is directly connected, FastEthernet1/1
O       10.1.0.0/24 [110/22] via 10.0.3.2, 00:01:03, FastEthernet1/1
O       10.1.1.0/24 [110/21] via 10.0.3.2, 00:01:03, FastEthernet1/1
O       10.1.2.0/24 [110/21] via 10.0.3.2, 00:01:03, FastEthernet1/1
O       10.1.3.0/24 [110/20] via 10.0.3.2, 00:01:03, FastEthernet1/1
  1. Aside from the next hop address, what else has changed on the routing table?

the routes have a higher Router Metrics, which is why they weren’t shown originally.

  1. View the OSPF database on R1 with the ‘show ip ospf database’ command. What is different between it and the RIP database? Why? OSPF has the IP address of all the routers in the network, including information abou who is advertising it and how many steps to get to it, unlike RIP, which only shows how to get to a specific network via a specific interface. In other words, OSPF has network topolgy information and RIP does not.

In short, RIP is a Distance Vector proto, while OSPF is a Link State proto.

Routing Protocol Metrics and Administrative Distance

  1. Enter the command below to remove OSPF on every router no router ospf 1
  2. Will R1 still have connectivity to R4? Yes, because RIP is still running
  3. What is the metric to the 10.1.1.0/24 network on R1?
show ip route
R 10.1.1.0/24 [120/2] via 10.0.3.2, 00:00:25, FastEthernet1/1

The metric is 2, because its two hops away

  1. Why is there only one route on R1 to the 10.1.1.0/24 network now? Because the other interface is shut down
  2. Make the required change so that there are two routes to the 10.1.1.0/24 network in the routing table on R1.
R2(config int)# no shut
  1. Enter the commands below on each router to provision a basic EIGRP configuration and enable EIGRP on every interface.
router eigrp 100
no auto-summary
network 10.0.0.0 0.255.255.255
!

  1. What changes do you expect to see in the routing tables? Why? I expect all the routes to be replaced with D routes that have an AD of 90, since EIGRP is preferred.

  2. Verify the changes to the routing table on R1.

  3. What is the metric to the 10.1.1.0/24 network on R1? 10.1.1.0/24 [90/33280] via 10.0.0.2, 00:00:51, FastEthernet0/0. The metric is 33280

  4. Why is there only one route to the 10.1.1.0/24 network on R1? Because EIGRP looks at hop count and bandwidth

  5. Disable RIP and EIGRP on R5 with the commands below.

R5(config)#no router rip
R5(config)#no router eigrp 100

  1. Configure the network so that there is still connectivity between all subnets if the link between R1 and R2 goes down. Accomplish this with six commands. Do not enable EIGRP on R5 but note that the routing protocol is expected to be enabled there in the future.

  2. What changes do you expect to see to the routing table on R1? The floating static route appears, but will not be used because it has a prefix length of 16, rather than the EIGRP one of 24

  3. Verify the changes to the routing table on R1.

  4. Verify that traffic from PC1 to PC3 still goes via R2.

  5. Shut down interface FastEthernet 0/0 on R2.

  6. What changes do you expect to see on R1’s routing table?

  7. Verify the changes to the routing table on R1.

  8. Verify connectivity between PC1 and PC3.

  9. Verify the traffic goes via R5.

  10. Bring interface FastEthernet 0/0 on R2 back up.

  11. Enter the commands below on R5 to provision a basic EIGRP configuration and enable EIGRP on every interface. R5(config)#router eigrp 100 R5(config-router)#no auto-summary R5(config-router)#network 10.0.0.0 0.255.255.255

Loopback Interfaces

  1. Configure loopback interface 0 on each router. Assign the IP address 192.168.0.x/32, where ‘x’ is the router number (for example 192.168.0.3/32 on R3.) R1(config)# int loopback 0 R1(config-if)# ip address 192.168.0.1 255.255.255.255
  2. Is there connectivity to the loopback interfaces from the PCs? Why or why not? No, because the interfaces don’t have routes to them.
  3. Enter the commands below on each router to include the loopback interfaces in EIGRP.

router eigrp 100 network 192.168.0.0 0.0.0.255 !

R1(config)#router eigrp 100 R1(config-router)#network 192.168.0.0 0.0.0.255 2) Verify the loopback interfaces are in the routing table on R1. 3) Verify connectivity from PC1 to the loopback interface on R5.

Adjacencies and Passive Interfaces

  1. Enter the command below to verify that R1 has established EIGRP adjacencies with R2 and R5. R1#show ip eigrp neighbors EIGRP-IPv4 Neighbors for AS(100) H Address Interface Hold Uptime SRTT RTO Q Seq (sec) (ms) Cnt Num 1 10.0.3.2 Fa1/1 14 00:17:21 33 198 0 16 0 10.0.0.2 Fa0/0 11 00:19:21 36 216 0 32
  2. Verify that traffic from R5 to the directly connected interfaces on R1 goes via the FastEthernet 0/1 interface.
  3. Enter the commands below to configure the loopback interface and the link to R5 as passive interfaces on R1. R1(config-if)#router eigrp 100 R1(config-router)#passive-interface loopback0 R1(config-router)#passive-interface fastethernet1/1
  4. What changes do you expect to see in the routing table on R5 and why?
  5. Verify the expected changes to the routing table on R5.

Graph View