CCNA Discovery 3 chapter 6

Lab 6.2.1 Configuring and Verifying Single Area OSPF

Step 1: Connect the equipment

Step 2: Perform basic configuration on Router 1

Step 3: Perform basic configuration on Router 2

Step 4: Perform basic configuration on Switch 1

Step 5: Configure the hosts with the proper IP address, subnet mask, and default gateway

Step 6: Verify that the network is functioning

a.     From the attached hosts, ping the FastEthernet interface of the default gateway router.

Was the ping from the first host successful? Jawab : ya

Was the ping from the second host successful? Jawab : ya

If the answer is no for either question, troubleshoot the router and host configurations to find the error. Ping again until they are both successful.

b.    Use the command show ip interface brief and check the status of each interface. What is the state of the interfaces on each router?

R1:

FastEthernet 0/0: up

Serial 0/0/0: up

Serial 0/0/1: administratively down

R2:

FastEthernet 0/0: up

Serial 0/0/0: up

Serial 0/0/1: administratively down

c.     Ping from one of the router connected serial interfaces to the other connected serial interface.

Was the ping successful? Jawab, ya

If the answer is no, troubleshoot the router configurations to find the error. Ping again until successful.

Step 7: Configure OSPF routing on R1

a.     Configure an OSPF routing process on router R1. Use OSPF process number 1 and ensure that all networks are in Area 0.

R1(config)#router ospf 1

R1(config-router)#network 192.168.1.128 0.0.0.63 area 0

R1(config-router)#network 192.168.15.0 0.0.0.3 area 0

R1(config-router)#end

b.    Examine the router running configuration. Did the IOS automatically add any lines under the router ospf 1 command? Jawab : ya

If so, what did it add? Jawab : log-adjacency-changes

c.     If there were no changes to the running configuration, enter the following commands:

R1(config)#router ospf 1

R1(config-router)#log-adjacency-changes

R1(config-router)#end

d.    Show the routing table for R1.

R1#show ip route

Are there any OSPF entries in the routing table now? Jawab : tidak

Why? Jawab : OSPF ti di konfigurasikan pada R2.

Step 8: Configure OSPF routing on R2

a.    Configure an OSPF routing process on router R2. Use OSPF process number 1 and ensure that all networks are in Area 0. R2(config)#router ospf 1

R2(config-router)#network 192.168.0.0 0.0.0.255 area 0

R2(config-router)#network 192.168.15.0 0.0.0.3 area 0

R2(config-router)#end

b.    Examine the R2 running configuration.

Did the IOS automatically add any lines under the router ospf 1 command? Jawaban: ya

If so, what did it add? Jawab : log-adjacency-changes

c.    If there were no changes to the running configuration, enter the following commands:

R2(config)#router ospf 1

R2(config-router)#log-adjacency-changes

R2(config-router)#end

d.    Show the routing table for R2.

R2#show ip route

Are there any OSPF entries in the routing table now? Jawab : ya

What is the metric value of the OSPF route to R1 Ethernet network 192.168.1.128? jawab:

Dengan bandwidth default 1544 Kbit pada Serial 0 / 0, biaya adalah 64 + 1 untuk Cepat
Jaringan Ethernet, memberikan biaya total rute 65.

What is the VIA address in the OSPF route? Jawab : 192.168.15.1

Are routes to all networks shown in the routing table? Jawab : ya

What does the O mean in the first column of the routing table? Jawab : Rute ini dipelajari oleh OSPF.

Step 8: Test network connectivity

Ping Host 2 from Host 1.

Was it successful? Jawab : ya

If the answer is no, troubleshoot to find the error. Ping again until successful.

Step 9: Reflection

a.     What is an advantage of using OSPF as the routing protocol in a network? Jawab:

termasuk yang OSPF efisien, menyediakan konvergensi cepat, dan skala
baik di jaringan yang besar

b.    What is a disadvantage of using OSPF as the routing protocol in a network? Jawab :

termasuk yang OSPF lebih sulit untuk mengkonfigurasi dan membutuhkan tepat
perencanaan.

Lab 6.2.2 Configuring OSPF Authentication

Step 1: Connect the equipment

Step 2: Perform basic configuration on the routers

Step 3: Configure and verify OSPF on the routers

Does the 192.168.1.0/24 network appear in the routing table of R1? Jawab : ya

Does the 192.168.0.0/24 network appear in the routing table of R2? Jawab : ya

Step 4: Configure and verify OSPF authentication

a.     Enable MD5 authentication in Area 0 on both routers.

R1(config)#router ospf 1

R1(config-router)#area 0 authentication message-digest

R2(config)#router ospf 1

R2(config-router)#area 0 authentication message-digest

b.    Enable OSPF authentication on S0/0/0 of R1.

R1(config)#interface s0/0/0

R1(config-if)#ip ospf message-digest-key 10 md5 secretpassword

c.     Using the show ip ospf neighbor command, view the neighbors known to R1.

R1#show ip ospf neighbor

Does R1 show any OSPF neighbors? Jawab:

Tidak ada atau mungkin tergantung pada seberapa banyak waktu yang telah berlalu. Mungkin melihat R2 sebagai tetangga selama beberapa detik sampai mati timer berakhir.

Why or why not? Jawab :

R1 dan R2 tidak sah satu sama lain.

d.    Watch the terminal output from R1 for several seconds.

What OSPF message was displayed when the MD5 authentication was set on R1 S0/0/0? Jawab:

*Oct 3 19:24:01.255: %OSPF-5-ADJCHG: Process 1, Nbr 192.168.2.2 on Serial0/0

from FULL to DOWN, Neighbor Down: Dead timer expired.

e.     Enable OSPF authentication on S0/0/0 of R2.

R2(config)#interface s0/0/0

R2(config-if)#ip ospf message-digest-key 10 md5 secretpassword

f.     Now, recheck the neighbour status between R1 and R2.

R1#show ip ospf neighbor

Do R1 and R2 have a neighbor relationship established now? Jawab : ya

What OSPF console message did you see after the MD5 authentication was set on R2 S0/0?

Jawab:

*Oct 3 18:29:19.095: %OSPF-5-ADJCHG: Process 1, Nbr 192.168.2.1 on Serial0/0

from LOADING to FULL, Loading Done

g.    Ping from Host 1 to Host 2 to verify connectivity.

Can Host 1 ping Host 2? Jawab : ya

Step 5: Reflection

a.     Why would OSPF authentication be configured in a network? Jawab :

Untuk mencegah akses tanpa izin ke routing informasi atau untuk mencegah tidak sah
injeksi informasi routing ke jaringan. Router di daerah OSPF hanya akan membentuk adjacencies dengan router lain yang telah mengatur otentikasi.

b.    Can one OSPF area have different OSPF configuration parameters than another area? Jawab :

Ya, konfigurasi pada basis per daerah.

c.     Can a single OSPF router have multiple authentication passwords configured? Jawab :

Ya, daerah yang berbeda dapat dikonfigurasi berbeda serta antarmuka yang berbeda.

Lab 6.2.3 Controlling a DR/BDR Election

Step 1: Connect the equipment

Step 2: Perform basic configuration on the routers.

Step 3: Configure single area OSPF routing on the routers

Step 4: Verify current OSPF operation

a.     Now that the Ethernet interfaces and OSPF have been configured, OSPF should be operational between the routers. Because this is a multi-access network, a DR/BDR election should have occurred.

b.  Use the show ip ospf neighbor command on all the routers to verify operation. The output should be similar to what is shown below.

R1#show ip ospf neighbor

Neighbor ID Pri State Dead Time Address Interface

192.168.1.2 1 FULL/BDR 00:00:38 192.168.1.2 FastEthernet0/0

192.168.1.3 1 FULL/DR 00:00:35 192.168.1.3 FastEthernet0/0

Do all routers show that they have established a neighbor relationship with the other routers? Jawab : ya

c.     Use the show ip ospf neighbor detail command on R1 to determine which routers are the DR and BDR.

Which router is the DR? jawab : R3

Which router is the BDR? Jawab : R2

What factor determined which router was the DR and which was the BDR in this scenario?

Step 5: Configure router loopback interfaces

Have the DR and BDR routers changed? Tidak : tidak

Which router is now the DR? jawab : R1

Which router is now the BDR? Jawab : R2

What factor determined which router was elected as the DR? jawab : Highest loopback address

Step 6: Use router interface priority to determine DR election

What is the default interface priority for the Fa0/0 interfaces? Jawab : 1

Use the show ip ospf neighbor command to determine the DR and BDR. Have the DR and the BDR changed? Jawab : tidak

Which router is now the DR? jawab : R2

Which router is now the BDR? Jawab: R1

Did the interface priority override the router ID in determining the DR/BDR? Jawab : ya

Step 7: Reflection

List the criteria used from highest to lowest for determining the DR on an OSPF network. Jawab:

Tertinggi adalah prioritas antarmuka. Berikutnya adalah router ID tertinggi yang ditentukan oleh alamat loopback tertinggi, atau dalam hal tidak ada loopbacks sedang diatur, itu adalah alamat antarmuka tertinggi aktif.

Lab 6.2.3 Configuring OSPF Parameters

Step 1: Connect the equipment

Step 2: Perform basic configuration on the routers

Step 3: Configure single area OSPF routing on the routers

Step 4: Verify current OSPF operation

a.     Use the show ip route command on all the routers to verify operation. The outputs should be similar to what is shown below. All networks should be listed in the routing table of each router.

Do all routers show that they have paths to all other networks? Jawab : ya

b.    Use the show interfaces serial 0/0/0 command to determine the bandwidth settings on the serial interfaces.

What is the current bandwidth setting of the interface? Jawab : 1544 Kbit

Do the interface bandwidth values match the clock rates set by the configuration Jawab : tidak

What path(s) would R1 take to get to the 10.0.0.0 network? jawab :Via R2 atau R3. Ada dua sama-biaya rute ke jaringan 10.0.0.0.

Step 5: Configure serial interface bandwidth settings

a.    Configure the bandwidth on the serial 0/0 interface of R1. R1

(config)#interface serial 0/0/0

R1(config-if)#bandwith 64

R1(config-if)#end

b.    Use the show interfaces serial 0/0/0 command on R1.

What is the bandwidth on S0/0 now? Jawab :

BW 64 Kbit

Serial0/0/0 is up, line protocol is up

Hardware is GT96K Serial

Internet address is 192.168.1.1/30

MTU 1500 bytes, BW 64 Kbit, DLY 20000 usec,

reliability 255/255, txload 1/255, rxload 1/255

c.    Again use the show ip route command on R1.

Has the routing table changed? Jawab : ya

Which path to the 10.0.0.0 network is now preferred? Jawab : Via 192.168.2.2 on R3

Why is that path preferred? Jawab : Lower cost than via R2

What is the cost shown to the 10.0.0.0 network? jawab : 128

How is this cost calculated? Jawab : There are two T1 (1.544 Mbps) speed links to get to the 10.0.0.0/30 network (R1 to R3 and R3 to the 10.0.0.0 net). The cost of each link is 64 (100,000,000 / 1,544,000). 64 + 64 = 128 total cost of route to 10.0.0.0. The route to the 10.0.0.0 network via R2 is now 1562 + 64 = 1626.

Step 6: Use ospf cost to determine route selection

a.    Use the show ip ospf interface command to determine the current cost for both R1 serial interfaces.

What is the cost for interface S0/0/0? Jawab: 1562

What is the cost for interface S0/0/1? Jawab : 64

b. On R1, configure the cost of the S0/1 interface with the ip ospf cost command. R1(config)#interface s0/0/1

R1(config)#ip ospf cost 2000

c.    Use the show ip route command on R1.

Has the routing table changed? Jawab : ya

            Which path to the 10.0.0.0 network is now preferred by R1? Jawab : melalui R2

Why is that path preferred? Jawab : Rute melalui R2 lebih disukai karena interface R1 pada jalur untuk R3 kini memiliki biaya yang lebih tinggi.

What is the cost shown to the 10.0.0.0 network now? Jawab : 1626

How is this cost calculated? Jawab: There is a T1 (1.544 Mbps) speed link from R1 to R3 and a 64 Kbps link from R3 to get to the 10.0.0.0/30 network. The cost of the T1 link is 64 (100,000,000 / 1,544,000) and the cost of the 64 Kbps link is 1562 (100,000,000 / 64,000). 64 + 1562 = 1626 total cost of route from R1 to 10.0.0.0. The router to the 10.0.0.0 network via R3 is now 2000 + 64 = 2064.

Step 7: Reflection

a.     What determines the path chosen by OSPF? Jawab : Lowest cost.

b.    What has a more direct effect on the OSPF cost of a link: the bandwidth setting or the ip ospf cost setting? Jawab : The ip ospf cost setting.

Lab 6.2.4 Part A: Configuring and Verifying Point-to-Point OSPF

Step 1: Connect the equipment

Step 2: Perform basic configurations on the routers

Step 3: Configure the router interfaces

Step 4: Verify IP addressing and interfaces

Step 5: Configure Ethernet interfaces of PC1, PC2, and PC3

Step 6: Configure OSPF on Router 1

Step 7: Configure OSPF on the R2 router

Step 8: Configure OSPF on the R3 router

Step 9: Configure OSPF router IDs

What is the router ID for R1? Jawab: 192.168.10.5

What is the router ID for R2? Jawab : 192.168.10.9

What is the router ID for R3? Jawab : 192.168.10.10

When the router is reloaded, what is the router ID for R1? Jawab : 10.1.1.1

When the router is reloaded, what is the router ID for R2? Jawab : 10.2.2.2

When the router is reloaded, what is the router ID for R3? Jawab : 10.3.3.3

Step 10: Verify OSPF operation

Step 11: Examine OSPF routes in the routing tables

Step 13: Reflection

What are some advantages of using OSPF as a routing protocol? Jawab ; VLSM and CIDR

Lab 6.2.4 Part B: Configuring and Verifying Multi-access OSPF

Step 1: Connect the equipment

Step 2: Perform basic configurations on the routers

Step 3: Configure and activate Ethernet and Loopback addresses

Step 4: Verify IP addressing and interfaces

Step 5: Configure OSPF on the DR router

Based on the loopback addresses assigned in Step 3, which router should be come the DR? Jawab : R3

What type of network has OSPF detected for this interface? Jawab : Network Type BROADCAST (Ethernet is a broadcast multi-access network)

What is the IP address of this interface? Jawab :192.168.1.3/24

What is the OSPF cost for this interface? Jawab :

1 (This is a FastEthernet interface and the OSPF cost for link is calculated as 100,000,000 /

100,000,000 = 1)

What is the router ID of this router? Jawab : 192.168.31.33

Step 6: Configure OSPF on the BDR router

What console message was displayed as a result of the OSPF commands on R2 and what does this

mean?  jawab :

An OSPF adjacency message displayed indicating an adjacency was formed with the R3 router (Nbr

192,168.31.33). When the hello packet is received, the neighbor relationship is formed.

00:08:51: %OSPF-5-ADJCHG: Process 1, Nbr 192.168.31.33 on

FastEthernet0/0 from LOADING to FULL, Loading Done

Step 7: Configure OSPF on the DRother router

Step 8: Use the OSPF priority to determine the DR and BDR

Step 9: Reflection

a.     When the OSPF process starts, what happens if there is no active interface on the router? Jawab: OSPF will not start.

b.    What can be done to ensure there will be an active interface on a router? Jawab : Configure a loopback interface.

c.     How are the DR and BDR elected in an OSPF network? jawab:

The DR is chosen with the highest OSPF priority value. The BDR is chosen with the second highest priority value. If the priority is the same, the OSPF election for DR is decided on the highest Router ID.

d.     What OSPF interface priority value prevents a router from being elected as a DR? jawab : 0

Lab 6.3.1 Configuring and Propagating an OSPF Default Route

Step 1: Connect the equipment

Step 2: Perform basic configurations on the routers

Step 3: Configure the ISP router

Step 4: Configure the Area 0 OSPF routers

Step 5: Configure the hosts with the proper IP address, subnet mask, and default gateway

Step 6: Verify connectivity

Ping from R2 to both the ISP and R1 routers.

Were the pings successful? Jawab : ya

If the pings were not successful, troubleshoot the router configurations until the ping is successful

Step 7: Configure OSPF routing on both Area 0 routers

a.     Configure OSPF routing on each router. Use OSPF process number 1 and ensure that all networks are in Area 0. R1(config)#router ospf 1

R1(config-router)#network 192.168.1.128 0.0.0.127 area 0

R1(config-router)#network 192.168.1.0 0.0.0.3 area 0

R2(config)#router ospf 1

R2(config-router)#network 192.168.0.0 0.0.0.255 area 0

R2(config-router)#network 192.168.1.0 0.0.0.3 area 0

Did the IOS version automatically add any lines under router OSPF 1? Jawab ; ya

b.    Show the routing table for R1.

Are there any entries in the routing table? Jawab : ya

Step 8: Test network connectivity

Ping the R1 host from the R2 host.

Was it successful? Jawab : ya

If the ping is not successful, troubleshoot as necessary

Step 9: Observe OSPF traffic

a.     At the privileged EXEC mode, enter the command debug ip ospf events and observe the output. You may have to wait at least 40 seconds for the hello packet to be sent before observations can be recorded.

Is there OSPF traffic?  Jawab : ya

What type of OSPF traffic is observed on the network? jawab : hello packets

b.    Turn off debugging by entering no debug ip ospf events or undebug all.

Step 10: Create a default route to the ISP

On R2 only, enter a static default route.

R2(config)#ip route 0.0.0.0 0.0.0.0 200.20.20.1

Step 11: Verify the default static route

Verify the default static route by looking at the R2 routing table.

Is the default route in the routing table? Jawab : ya

Step 12: Verify connectivity from the R2 router

a.    Verify connectivity from R2 by pinging the ISP Serial 0/0/1 interface from the R2 router.

Is the ping successful? Jawab : ya

b.    Next, on the host attached to R2, open a command prompt and ping the Serial 1 interface on the ISP router.

Is the ping successful? Jawab : ya

c.    This time, ping the loopback interface address of the ISP router, which represents the ISP connection to the Internet.

Is the ping successful? Jawab : ya

All of these pings should be successful. If they are not, troubleshoot the configurations on the host and on the R2 and ISP routers.

Step 13: Verify connectivity from the R1 router.

Verify the connection between the ISP and R1 by pinging the Serial 0/0/1 interface of the ISP router on R2.

Is the ping successful? Jawab : tidak

If yes, why?

If not, why not? Jawab : There is no route to the ISP router.

Step 14: Redistribute the static default route

Propagate the gateway of last resort to the other routers in the OSPF domain. At the configure router prompt on R2, enter

default-information originate.

R2(config-router)#default-information originate

Is there now a default route on R1?  Jawab : ya

What is the address of the gateway of last resort? Jawab: 192.168.1.2

There is an O*E2 entry in the routing table. What type of route is this?  Jawab: OSPF External type 2

Can the ISP server address at 138.25.6.33 be pinged from both workstations? Jawab : ya

If no, troubleshoot both hosts and all three routers.

Step 15: Reflection

a.     How does OSPF reach networks outside of the domain? Jawab: OSPF must know about the network or OSPF must have a default route.

b.    What does a router use to generate a gateway of last resort? Jawab : Default route

Lab 6.3.2 Configuring OSPF Summarization

Step 1: Connect the equipment

Step 2: Perform basic configurations on the routers

Step 3: Perform basic configurations on the switches

Step 4: Configure the hosts with the proper IP address, subnet mask, and default gateway

Step 5: Configure OSPF routing with default summarization

From the network commands, which interfaces are participating in OSPF routing? Jawab: S0/0/0, S0/0/1.

Step 6: Configure and redistribute a default route for Internet access

Step 7: Verify the routing configuration

a.     How can you tell from the routing table that the subnetted network shared by the corporate routers has a pathway for traffic destined for the Internet? Jawab : There is a gateway of last resort, and the default route shows up in the table.

b.    View the routing tables on R2 and R3.

How is the pathway for Internet traffic provided in their routing tables? Jawab : There is a gateway of last resort leading to R3, and the default route shows up as a distributed OSPF

route.

Step 8: Verify connectivity

a.     Simulate sending traffic to the Internet by pinging from the host PCs to 209.165.201.1.

Were the pings successful? Jawab : ya

b.    Verify that hosts within the subnetted network can reach each other by pinging between Host 1 and Host 2.

Were the pings successful? Jawab : ya

Step 9: Configure OSPF summarization

a.     Compute a summary route for the corporate subnetworks. The networks have been assigned contiguously:

192.168.10.0

192.168.10.32

192.168.10.64

192.168.10.68

192.168.10.72

What is the one summary route that can be used to advertise all of these subnets? Jawab : 192.168.10.0/25

Which router will be reporting this summary route to the ISP? Jawab : border

Step 10: Recheck routing tables to verify the summarization

View the effects of summarization using the following commands:

Border#show ip ospf summary-address

Do the routers still have a route for Internet traffic? Jawab : ya

Does Border have to report changes in individual subnets to the ISP? Jawab : tidak

If the connection to one particular subnet in this area went down, would the summary route be affected? Jawab : tidak

Think about your answers to the previous questions. What advantage do you see in using summarization in this network

Step 11: Reflection

List three effects of using summarization within an OSPF area.jawab: Answers can include: smaller routing table, lower memory and processor requirements, fewer lookups

needed.