CSCO 220 Modules 1 & 2 Lab Packet-OSPF with Questions

Module 1: Single-Area OSPF Concepts Module 2: Single-Area OSPF Configuration For some of this packet you will need to have access to your account on the Netacad website . Grading Rubric Your Score Packet complete, answers correct, submitted on-time. 4 Packet complete, answers mostly correct, submitted on-time. 3 Packet mostly complete, answers mostly correct, submitted on-time. 2 Packet mostly complete, answers mostly correct, submitted late. 1  For the Packet Tracer exercises located below, go to the Netacad link, click on it and go to the module this lab packet applies to. Click on the section where the Packet Tracer activity is located, download the Packet Tracer activity and follow the instructions included with the Packet Tracer activity  Perform any Netlab assignments listed below, be sure to post your answers in RED  Follow along in the PT assignments and post your answers to the questions in RED  Post a Packet Tracer screen shot ONLY of the name of the lab and the completion score (not the network or anything else unless requested). Make the screenshot the size of the page so I can easily read it using my grading software Packet Tracer 2.2.13-Point-to Point Single-Area OSPFv2 Configuration. Post a screenshot of the completion screen below, make it the width of the page and answer the questions in RED. How many statements are required to configure OSPF to route all the networks attached to router R1? © 2023 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public. Page 1 of 8 CSCO 220

Three The LAN attached to router R1 has a /24 mask. What is the equivalent of this mask in dotted decimal representation? 255.255.255.0 Subtract the dotted decimal subnet mask from 255.255.255.255. What is the result? 0.0.0.255 What is the dotted decimal equivalent of the /30 subnet mask? 255.255.255.252 Subtract the dotted decimal representation of the /30 mask from 255.255.255.255. What is the result? 0.0.0.3 Which interfaces on R3 should be configured with OSPF? G0/0/0, S0/1/0, and S0/1/1 Which interfaces on R1, R2, and R3 are a LAN interfaces? G0/0/0 on all three routers Use show commands to verify the network and passive interface configuration of the OSPF process on each router (post output): Packet Tracer 2.3.11-Determine the BR and BDR. Post a screenshot of the completion screen below, make it the width of the page. Answer the questions in RED. Which router is the DR? RC Which router is the BDR? RB What is the OSPF state of router RA? DROTHER According to the debug output, which router was elected DR and which router was elected BDR? RB is now DR and RA is now BDR. © 2023 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public. Page 2 of 8

Were any of the pings successful? No What message did you receive, and which device issued the message? “Destination host unreachable.” R2 issued the message. Question: What statement is present in the routing tables that indicates that the pings to the Web Server will fail? “Gateway of last resort is not set” Packet Tracer 2.6.6-Verify Single-Area OSPFv2. Post a screenshot of the completion screen below, make it the width of the page and answer the questions in RED. How did router R1 receive the default route? It was learned through OSPF. From which router did R1 receive the default route? R2 How can you filter the output of show ip route to show only the routes learned through OSPF? Use the “ show ip route ospf” command. Which routers have formed adjacencies with router R1 ? R2 and R3 What are the router IDs and state of the routers shown in the command output? 2.2.2.2 – Full/- 3.3.3.3 – Full/- Are all of the adjacent routers shown in the output? Yes How did router R2 learn the default route to the ISP? © 2023 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public. Page 4 of 8

It was statically configured. Netlab 2.7.2. Single-Area OSPFv2 Configurations. Post your answers in red. 1. Topology 2. Addressing Table Device Interface IP Address Subnet Mask R1 G0/0/1 10.53.0.1 255.255.255.0 R1 Loopback1 172.16.1.1 255.255.255.0 R2 G0/0/1 10.53.0.2 255.255.255.0 R2 Loopback1 192.168.1.1 255.255.255.0 © 2023 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public. Page 5 of 8

Create a banner that warns anyone accessing the device that unauthorized access is prohibited. Save the running configuration to the startup configuration file. Close configuration window Configure and Verify Single-Area OSPFv2 for basic operation. Configure interface addresses and basic OSPFv2 on each router. Configure interface addresses on each router as shown in the Addressing Table above. Open configuration window Enter OSPF router configuration mode using process ID 56. Configure a static router ID for each router (1.1.1.1 for R1, 2.2.2.2 for R2). Configure a network statement for the network between R1 and R2 placing it in area 0. On R2 only , add the configuration necessary to advertise the Loopback 1 network into OSPF area 0. Verify OSPFv2 is operational between the routers. Issue the command to verify R1 and R2 have formed an adjacency. Question: Which router is identified as the DR? Which is the BDR? What was the selection criteria? R1 was configured first and was speaking OSPF before R2. So, during the OSPF election only R1 was configured for OSPF and became the DR. After R2 was configured for OSPF, it became the BDR on the Gigabit segment. The router with the highest router ID is used in the selection of DR and BDR. On R1, issue the show ip route ospf command to verify that the R2 Loopback1 network is present in the routing table. Notice the default behavior of OSPF is to advertise a loopback interface as a host route using a 32 bit mask. Ping the R2 Loopback 1 interface address from R1. The ping should succeed. close configuration window Optimize the Single-Area OSPFv2 configuration Implement various optimizations on each router. Open configuration window On R1, configure the interface G0/0/1 OSPF priority to 50 to ensure R1 is the Designated Router. Configure the OSPF timers on the G0/0/1 of each router for a hello timer of 30 seconds. On R1, configure a default static route that uses interface Loopback 1 as the exit interface. Then, propagate the default route into OSPF. Note the console message after setting the default route. On R2 only, add the configuration necessary for OSPF to treat R2 Loopback 1 like a point-to-point network. This results in OSPF advertising Loopback 1 using the interface subnet mask. On R2 only , add the configuration necessary to prevent OSPF advertisements from being sent to the Loopback 1 network. Change the reference bandwidth on each router to 1Gbs. After this configuration, restart OSPF using the clear ip ospf process command. Note the console message after setting the new reference bandwidth. Verify OSPFv2 optimizations are in place. Issue the show ip ospf interface g0/0/1 command on R1 and verify that the interface priority has been set to 50 and that the time intervals are Hello 30, Dead 120, and the default Network Type is Broadcast On R1, issue the show ip route ospf command to verify that the R2 Loopback1 network is present in the routing table. Note the difference in the metric between this output and the previous output. Also note the mask is now 24 bits as opposed to the 32 bits previously advertised. On R2, issue the show ip route ospf command. The only OSPF route information should be the default route R1 is propagating. Ping the R1 Loopback 1 interface address from R2. The ping should succeed. © 2023 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public. Page 7 of 8

Question: Why is the OSPF cost for the default route different than the OSPF cost at R1 for the 192.168.1.0/24 network? A default static route imported into OSPF is given the metric type of “E2” or External Type 2 by default. An “E2” by default, keeps the same OSPF cost across the entire OSPF network. In this case, the metric for the default route was 1, so it has a metric of 1 everywhere in the OSPF 56 network. The 192.168.1.0 /24 network is an internal OSPF route whose metric is increasing. Close configuration window 6. Router Interface Summary Table Router Model Ethernet Interface #1 Ethernet Interface #2 Serial Interface #1 Serial Interface #2 1800 Fast Ethernet 0/0 (F0/0) Fast Ethernet 0/1 (F0/1) Serial 0/0/0 (S0/0/0) Serial 0/0/1 (S0/0/1) 1900 Gigabit Ethernet 0/0 (G0/0) Gigabit Ethernet 0/1 (G0/1) Serial 0/0/0 (S0/0/0) Serial 0/0/1 (S0/0/1) 2801 Fast Ethernet 0/0 (F0/0) Fast Ethernet 0/1 (F0/1) Serial 0/1/0 (S0/1/0) Serial 0/1/1 (S0/1/1) 2811 Fast Ethernet 0/0 (F0/0) Fast Ethernet 0/1 (F0/1) Serial 0/0/0 (S0/0/0) Serial 0/0/1 (S0/0/1) 2900 Gigabit Ethernet 0/0 (G0/0) Gigabit Ethernet 0/1 (G0/1) Serial 0/0/0 (S0/0/0) Serial 0/0/1 (S0/0/1) 4221 Gigabit Ethernet 0/0/0 (G0/0/0) Gigabit Ethernet 0/0/1 (G0/0/1) Serial 0/1/0 (S0/1/0) Serial 0/1/1 (S0/1/1) 4300 Gigabit Ethernet 0/0/0 (G0/0/0) Gigabit Ethernet 0/0/1 (G0/0/1) Serial 0/1/0 (S0/1/0) Serial 0/1/1 (S0/1/1) Note : To find out how the router is configured, look at the interfaces to identify the type of router and how many interfaces the router has. There is no way to effectively list all the combinations of configurations for each router class. This table includes identifiers for the possible combinations of Ethernet and Serial interfaces in the device. The table does not include any other type of interface, even though a specific router may contain one. An example of this might be an ISDN BRI interface. The string in parenthesis is the legal abbreviation that can be used in Cisco IOS commands to represent the interface. © 2023 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public. Page 8 of 8