Cisco Discovery 3 Module 9 Course Curriculum Picture Descriptions Module 9.0 ? Chapter Introduction 9.0.1 Introduction One Diagram Diagram 1, Slideshow Introduction Enterprise networks can have problems that range from poor performance to unreachable resources. Network monitoring, proactive maintenance, effective troubleshooting methods and an awareness of failure domains can help to minimize network downtime. Network problems can involve a variety of technologies including LAN switching, routing protocols, WAN links and ACLs After completion of this chapter, you should be able to: Explain the importance of uptime and the types of issues that cause failure. Isolate and correct switching problems. Isolate and correct routing issues. Isolate and correct WAN configurations. Isolate and correct ACL issues. 9.1 - Understanding the Impact of Network Failure 9.1.1 - Enterprise Network Requirements Four Diagrams Diagram 1, Image Silhouette of a group of people. Diagram 2, Image A satellite image of the earth showing a storm. Diagram 3, Image A network design showing three layered hierarchical leveled network structure, which incorporates good design characteristics such as redundancy. Diagram 4, Image Image of a network showing its headquarters and the availability of a backup site. 9.1.2 - Monitoring and Proactive Maintenance Five Diagrams Diagram 1, Image Picture of a technician work on a rack of equipment. Diagram 2, Image Diagram depicts 2 screen captures of the ping command Baseline On FEB 2, 2007 08:14:43 a ping command to the following IP was made 10.66.254.159. The delay times for the ping were all 1 millisecond. Congestion problems? On MAR 17, 2007 14:41:06 a ping command to the following IP was made 10.66.254.159. The delay times for the ping were all 6 millisecond. Diagram 3, Image A man sitting at his work station is connected to a small network of three routers. He thinks to himself ?Should I use ping? tracert? Packet Sniffing?? Diagram 4, Image Image shows a man sitting at a workstation titled Management Station, Network Management Protocol. He is connected to a small network. The following items on the network are labeled as follows, one of the routes is labeled Management Agent and Router MIB, one of the switches is labeled Management Agent and Switch MIB and one of the servers is labeled Central MIB. Diagram 5, Packet Tracer Exploration 9.1.3- Troubleshooting and the Failure Domain Four Diagrams Diagram 1, Image Image shows a corporate network and the availability of Hot Swappable Spares such as servers, routers and switched. Diagram 2, Animation A hacker sends a packet through the Internet to an enterprise network but it is stopped by the firewall. The hacker thinks to himself ?The firewall is stopping me from entering the company.? Someone within the enterprise thinks to himself ?The firewall just went down.? The person in the enterprise then thinks to himself ?To get the network up quickly, we will replace the firewall with a router.? The hacker sends another packet through the internet to the enterprise and thinks to himself ?The firewall must be down, I can access the network easily now.? The hacker then has easy access to the network. Diagram 3, Image Image shows the different effects that the failure of a level two switch and a level 3 router have on a network. The switch shows a small failure domain and the router a much larger failure domain. Diagram 4, Activity Determine how many hosts will be unable to connect to the Internet when each router fails. The Internet is connects to R1, which connects to R2. R2 connects to R3 and R5. R3 connects to 2 switches each switch has two hosts. R3 also connects back to R5. R5 connects to R4 and R6. R4 connects to 3 switches. R6 connects to 3 switches. R3 connects to 2 switches. Each switch is connected to 2 hosts. Routers: R1: (2, 4, 6, 10, 12 or 16?) R2: (2, 4, 6, 10, 12 or 16?) R3: (2, 4, 6, 10, 12 or 16?) R4: (2, 4, 6, 10, 12 or 16?) R5: (2, 4, 6, 10, 12 or 16?) R6: (2, 4, 6, 10, 12 or 16?) 9.1.4 - Troubleshooting Process Three Diagrams Diagram 1, Image Diagram contains no useful information Diagram 2, Image OSI Model Application layer Associated with specific services such as FTP and DNS If resources are unreachable or unusable, while the physical, data link, network, and transport layers are functional the problem is associated with this layer Presentation Layer Responsible for data representation Includes compression and encryption If data is being reliably transmitted across the network but is unreadable on the receiving end, suspect the presentation layer Verify that any encryption keys match and are properly configured Session Layer Responsible for establishing, maintaining and terminating end to end communication sessions between applications Related to synchronization and flow control An application server failing during a communication session, could generate problems at the session layer Transport Layer Uses port numbers to identify the type of traffic being carried in the conversation Misconfigured ACLs are a common problem at this layer Network Layer Involved with logical addressing and best path determination Layer 3 addressing and routing problems are associated with this layer The most common problems are improperly configured addresses and improper routing information Misconfigured ACLs are an issue at the network layer Data Link Layer Concerned mainly with the encapsulation of data Mismatched encapsulation is one of the most common issues at this layer Includes improper conversion of Layer 2 encapsulation as the frames move across the network Improperly configured switch ports and Layer 2 addressing issues are also common Misconfigured VLANs can generate problems at Layer 2 Physical Layer Concerned with physical connectivity Common issues include damaged or improper cabling, physical damage to ports and power issues In wireless networks, antennas are physical layer devices as is the RF medium Any loss in signal strength or interference is considered a layer 1 problem Diagram 3, Activity Match each problem to the correct layer of the OSI model with which it is best associated. A: Vida is unable to connect to a web server even though she is able to ping and tracert to the same address. B: Carlos misconfigures an ACL to filter DNS traffic when he meant to filter FTP traffic. C: Gustavo configures PPP encapsulation on one end of the serial link to the ISP and the link goes down. D: Tyrone checks the MAC address table on the switch and notices that the value for one of the connected hosts is not correct. E: Suresh mistypes the IP address on the router interface. F: Rebecca installs the wrong type of antenna on the AP. Module 9.2 ? Troubleshooting Switching and Connectivity Issues 9.2.1 ? Troubleshooting Basic Switching 5 Diagrams Diagram 1, Image The diagram depicts two rack mount switches that have connections stemming out of the RJ-45 ports. There are 16 connections to individual client computers. Diagram 2, Image The diagram depicts two switches named S1 and S2 directly connected to each other by an Ethernet link from Fa0/2 on both switches. Switch S1 has Fa0/4 and Fa0/6 in use. Switch S2 has its Fa0/1 port in use and an Ethernet link between S2 and Router R1 has been established. Router R1 has a serial link between itself and the WAN. The command ?show mac-address-table? has been issued and the output for this command is listed below: MAC Address Table VLAN MAC Address Type Ports All 000.d.6563.bd00 Static CPU All 0100.0ccc.cccc Static CPU All 0100.0ccc.cccd Static CPU All 0100.0ccc.dddd Static CPU 1 000d.29a0.88e0 Dynamic Fa0/2 1 000d.6563.0582 Dynamic Fa0/2 1 0010.a4fa.b23e Dynamic Fa0/6 1 00b0.d04d.01f7 Dynamic Fa0/4 101 000d.29a0.88e0 Dynamic Fa0/2 101 000d.6563.0582 Dynamic Fa0/2 102 000d.29a0.88e0 Dynamic Fa0/2 102 000d.6563.0582 Dynamic Fa0/2 103 000d.29a0.88e0 Dynamic Fa0/2 103 000d.6563,0582 Dynamic Fa0/2 Total MAC addresses in this criterion: 14 Diagram 3, Image The diagram depicts switch S1 with the Fast Ethernet ports Fa0/4, Fa0/2 and Fa0/6 in use. Fa0/2 on Switch S1 is directly connected to Switch S2?s Fa0/2 is directly connected to S1?s Fa0/2. S2 has its Fa0/1 directly connected to Router R1?s Fa0/1 and R1?s serial interface S0/1 is connected by serial link to the WAN cloud. Items of interest are highlighted: Fast Ethernet0/6 is up, line protocol is up (connected) Hardware is Fast Ethernet, address is 000d.6563.bd06 (bia 000d.6563.bd06) Output omitted Full-duplex, 100Mb/s Diagram 4, Image The diagram depicts switch S1 with the Fast Ethernet ports Fa0/4, Fa0/2 and Fa0/6 in use. Fa0/2 on Switch S1 is directly connected to Switch S2?s Fa0/2 is directly connected to S1?s Fa0/2. S2 has its Fa0/1 directly connected to Router R1?s Fa0/1 and R1?s serial interface S0/1 is connected by serial link to the WAN cloud. The command, ?show spanning-tree? is entered and executed for each of the Switches, the output of this command can be viewed in the lab attached to this module. Diagram 5, Packet Tracer Exercise 9.2.2 ? Troubleshooting VLAN Configuration Issues 4 Diagrams Diagram 1, Image The diagram depicts switch S1 directly connected to switch S2 and the connection is established between the two Fast Ethernet ports Fa0/2 on both switches. S2 has its Fast Ethernet Fa0/1 directly connected to Router R1?s Fa0/0. R1 has its serial interface S0/1 connected by serial link to the WAN cloud. The commands, show vlan, show vlan brief and show vlan id 101 are listed at the bottom of the image and can be pressed to view the output of these commands. The outputs of these commands can be viewed in the lab attached to this module once configuration has taken place. Diagram 2, Image The diagram depicts switch S1 directly connected to switch S2 and the connection is established between the two Fast Ethernet ports Fa0/2 on both switches. S2 has its Fast Ethernet Fa0/1 directly connected to Router R1?s Fa0/0. R1 has its serial interface S0/1 connected by serial link to the WAN cloud. The commands, show ip interfaces brief and show ip route are listed at the bottom of the image and can be pressed to view the output of these commands. The outputs of these commands can be viewed in the lab attached to this module once configuration has taken place. Diagram 3, Animation The diagram depicts a woman sitting at her desktop computer and it is directly connected to switch S1 which is acting as the Access Port and has the Native VLAN 10. Switch S1 is connected to Switch S2 which has the Native VLAN 14. The connection between S1 and S2 are using Trunk Ports. The woman issues the command, ?show CDP neighbors? Which is sent on VLAN10, at S2 the message is relabled VLAN 14.The response starts out from S@ labeled VLAN 14 and is relabled at S1 with VLAN 10. Diagram 4, Packet Tracer Exercise 9.2.3 ? Troubleshooting VTP 3 Diagrams Diagram 1, Image The diagram depicts switch S1 with its three Fast Ethernet ports Fa0/4, Fa0/6 and Fa0/2 in use. Switch S2 is connected to Switch S1 by Fa0/2 on both switches. Switch S2 has its Fa0/1 in use and connected to Router R1?s Fa0/0. Router R1?s serial interface S0/1 is in use and connected by serial link to the WAN cloud. Two outputs for the command ?show vtp status? are listed and the outputs of these commands are shown. The outputs of these commands for each switch can be viewed in its entirety by configuring VTP and then using to the ?show? command to view the configuration changes in the lab attached to this module. Diagram 2, Animation The VTP server switch (S3) connects to the client switch (S1). S1, fa0/2 connects to the server switch (S2) fa0/2. S2 fa0/1 connects to Router R1 fa0/0 . R1 S0/1 connects by serial link to the WAN cloud. The commands, ?No VTP password? and ?VTP password? are able to be selected from the bottom of the page as radio buttons. When ?No VTP Password? is selected, S2 tells the client switch about VLANs 100, 101,102 and 103. It states this is version 5. The client responds ?I now know about these VLANs? The VTP server switch now states it has information about other VLANs and sends notification to other switches (as version 17) when S1 receives the update, it notes that version 17 is higher than 5 so notifies other connected switches of the update. When ?VTP password? is selected, sends revision number information as well as a password that the destination switch must recognize before accepting the revision number information. If the switch does not recognize the password that accompanies the revision number information, it rejects the update. Diagram 3, Packet Tracer Ecercise Module 9.3 ? Troubleshooting Routing Issues 9.3.1 ? RIP Issues Four Diagrams Diagram 1, Image RIP Issues The picture depicts a network, and shows a screen capture of some of the various show commands, the key/highlighted parts of which are as follows: Network Two Routers(R1, R2) R1 is connected to R2 via serial link (R1: S0/0/0, R2: S0/0/0, network: 172.20/1.0/30) R1 has network 192.168.1.0/24 on interface Fa0/0 R2 has network 192.168.2.0/24 on interface Fa0/0 Show ip protocols Default version control: send version 2, receive version 2 Routing for Networks: 172.20.0.0 192.168.1.0 Show running-config Interface FastEthernet0/0 Description LAN gateway for 192.168.1.0 Ip address 192.168.1.1 255.255.255.0 Interface Serial 0/0/0 Description WAN link to R2 Ip address 172.20.1.1 255.255.255.252 Router rip Version 2 Passive-interface FastEthernet0/0 Network 172.20.0.0 Network 192.168.1.0 Show interface MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec, Auto-duplex, Auto Speed, 100BaseTX/FX Show ip interface Multicast reserved groups joined: 224.0.0.9 Show ip route Debug ip rip *Sep 12 21:09:16 399: RIP: received v2 update from 172.20.1.2 on Serial0/0/0 Diagram 2, Image RIP Issues The picture depicts a network, and shows a screen capture of some of the various show commands some parts of which are highlighted as follows Network Two Routers(R1, R2) R1 is connected to R2 via serial link(R1: S0/0/0, R2: S0/0/0, network: 172.20/1.0/30) R1 has network 192.168.1.0/24 on interface Fa0/0 R2 has network 192.168.2.0/24 on interface Fa0/0 R! show ip protocol Send version 2, receive version 2 Interface ? Serial0/0/0 Send ? 2 Recv ? 2 Triggered - RIP ? Key-chain ? R2 show ip protocol Send version 1, receive any version Interface ? Serial0/0/0 Send ? 2 Recv ? 1 2 Triggered - RIP ? Key-chain ? R1 debug ip rip Sending v2 update to 224.0.0.9 via Serial0/0/0 (172.20.1.1) R1 show ip route Diagram 3, Packet Tracer Exercise Diagram 4, Hands On Lab 9.3.2 ? EIGRP Issues Three Diagrams Diagram 1, Image The picture depicts a network, and shows a screen capture of some of the show commands. The key/highlighted parts of which are as follows: Network Three Routers(R1, R2, R3) R1 is connected to R2 via Serial link(R1: S0/0/0, R2:S0/0/0, Network: 172.20.1.0/30) R1 is connected to R3 via Serial link(R1: S0/0/1, R3: S0/0/1, Network: 172.20.1.4/30) R2 is connected to R3 via Serial link(R2: S0/0/1, R3: S0/0/0, Network: 172.20.1.8/30) R1 has network 192.168.1.0/24 attached to the Fa0/0 interface R2 has network 192.168.2.0/24 attached to the Fa0/0 interface R3 has network 192.168.3.0/24 attached to the Fa0/0 interface Certain sections of the various show commands have been highlighted, which include: Show ip route D 192.168.2.0/24 [90/2172416] via 172.20.1.2, 00:11:53, Serial0/0/0 D 192.168.3.0/24 [90/2172416] via 172.20.1.6, 00:11:53, Serial0/0/1 Show ip protocols Redistributing: eigrp 101 Routing for Networks: 1722.20.1.0/30 172.20.1.4/30 192.168.1.0 show ip interface Multicast reserved groups joined: 224.0.0.10 Show running config Interface FastEthernet0/0 Description LAN gateway for 192.168.1.0 net Ip address 192.168.1.1 255.255.255.0 Interface serial0/0/1 Description WAN link to R3 Ip address 172.20.1.5 255.255.255.252 Router eigrp 101 Network 172.20.1.0 0.0.0.3 Network 172.20.1.4 0.0.0.3 Network 192.168.1.0 No auto-summary Show ip eigrp neighbors H ? 1 Address - Num ? 172.20.1.2 Interface - Se0/0/0 Hold - 10 Uptime - 00:13:59 SRTT - 1 RTO - 200 Q - 0 Seq - 18 H ? 0 Address ? 172.20.1.6 Interface ? Se0/0/1 Hold ? 12 Uptime - 00:15:29 SRTT ? 1 RTO ? 200 Q ? 9 Seq ? 21 Show ip eigrp topology Show ip eigrp traffic Hellos sent/received: 1102/469 Updates sent/received: 10/19 Queries sent/received: 0/5 Replies sent/received: 5/0 Acks sent/received: 20/11 Debug eigrp packets Debug ip eigrp Diagram 2, Image The picture depicts a network, and shows a screen capture of some of the show commands some of which are highlighted as follows Network Three Routers(R1, R2, R3) R1 is connected to R2 via Serial link(R1: S0/0/0, R2:S0/0/0, Network: 172.20.1.0/30) R1 is connected to R3 via Serial link(R1: S0/0/1, R3: S0/0/1, Network: 172.20.1.4/30) R2 is connected to R3 via Serial link(R2: S0/0/1, R3: S0/0/0, Network: 172.20.1.8/30) R1 has network 192.168.1.0/24 attached to the Fa0/0 interface R2 has network 192.168.2.0/24 attached to the Fa0/0 interface R3 has network 192.168.3.0/24 attached to the Fa0/0 interface R1 ? show ip route R2 ? show ip route R1 ? show ip eigrp neighbors IP-EIGRP neighbors for process 101 R2 ? show ip eigrp neighbors IP-EIGRP neighbors for process 11 Diagram 3, Packet Tracer Exercises 9.3.3 ? OSPF Issues Diagram 1, Image The picture depicts a network, and shows a screen capture of some of the show commands some of which are highlighted as follows Network Three Routers(R1, R2, R3) R1 is connected to R2 via Serial link(R1: S0/0/0, R2:S0/0/0, Network: 172.20.1.0/30) R1 is connected to R3 via Serial link(R1: S0/0/1, R3: S0/0/1, Network: 172.20.1.4/30) R2 is connected to R3 via Serial link(R2: S0/0/1, R3: S0/0/0, Network: 172.20.1.8/30) R1 has network 192.168.1.0/24 attached to the Fa0/0 interface R2 has network 192.168.2.0/24 attached to the Fa0/0 interface R3 has network 192.168.3.0/24 attached to the Fa0/0 interface Show ip ospf Displays information about the OSPF routing process, areas, number of interfaces, authentication and how often the SPF algorithm executes. SPF executions indicate a change in the topology, such as a router being added or a network link going down. Routing Process ?ospf 1? with ID 192.168.1.1 Area BACKBONE (0) Number of interfaces in this area is 3 Area has no authentication SPF algorithm last executed 00:08:48.240 ago SPF algorithm executed 6 times Show ip ospf neighbor Displays neighbor ID, the IP addresses of the neighbor interfaces and the interface on which they were learned. Useful for troubleshooting adjacency problems. Neighbor ID - 192.168.3.1 Pri ? 0 State ? FULL/ - Dead Time ? 00:00:31 Address ? 172.20.1.6 Interface ? Serial0/0/1 Neighbor ID ? 192.168.2.1 Pri ? 0 State ? FULL/ - Dead Time ? 00:00:37 Address ? 172.20.1.2 Interface ? Serial0/0/0 Show ip oasp interface Displays Router ID, Network Type, link cost, State, Interface priority, DR ID, Timer intervals configured and Neighbor adjacency information. Internet Address 192.168.1.1/24, Area 0 Process ID 1, Router ID 192.168.1.1, Network Type Broadcast, Cost: 1 Neighbor Count is 0, Adjacent neighbor count is 0 Process ID 1, Router ID 192.1668.1.1, Network Type POINT T OPOINT, Cost: 6 Debug ip ospf events Displays real-time OSPF exchanges between neighbors, including helllos and LSAs *Sep 14 17:23:00.351: OSPF: Send hello to 224.0.0.5 area 0 on Serial0/0/1 from 172.20.1.5 *Sep 14 17:23:00.655: OSPF: Rcv hello from 192.168.3.1 area 0 from Serial0/0/1 1 debug ip ospf packet Displays real-time information for each OSPF packet received. Diagram 2, Activity Determine whether the statements are True or False for the given scenarios Scenario 1 R1#show ip protocols Routing Protocol is ?ospf1? Outgoing update filter list for all interfaces is not set Incoming update filter list for all interfaces is not set Router ID 192.168.1.1 Number of areas in this router is 1. 1 normal 0 stub 0 nssa Maximum path: 4 Routing for Networks: 172.20.1.0 0.0.0.3 area 0 reference bandwidth unit is 100 mbps Routing Information Sources: Gateway Distance Last Update 192.168.3.1 110 01:44:03 192.168.2.1 110 01:44:03 Distance: (default is 110) Network Three Routers(R1, R2, R3) R1 is connected to R2 via Serial link(R1: S0/0/0, R2:S0/0/0, Network: 172.20.1.0/30) R1 is connected to R3 via Serial link(R1: S0/0/1, R3: S0/0/1, Network: 172.20.1.4/30) R2 is connected to R3 via Serial link(R2: S0/0/1, R3: S0/0/0, Network: 172.20.1.8/30) R1 has network 192.168.1.0/24 attached to the Fa0/0 interface R2 has network 192.168.2.0/24 attached to the Fa0/0 interface R3 has network 192.168.3.0/24 attached to the Fa0/0 interface 1. The highest numbered interface IP address on this router is 192.168.3.1 2. This router has 3 network statements defined in the OSPF routing process. 3. Network 172.20.1.4 0.0.0.3 has 4 IP addresses in it 4. The OSPF Administrative Distance is 100 5. When calculating link cost on this router the reference bandwidth of 100,000,000 is divided by the bandwidth of the interface. Scenario 2 Exhibit R1#show ip ospf ***Some output omitted *** Routing Process ospf 1? with ID 192.168.1.1 Start time: 00:08:40.340, Time elapsed: 00:17:56.552 Number of areas in this router is 1. 1 normal 0 stub 0 nssa Number of areas transit capable is 0 External flood list length 0 Area BACKBONE (0) Number of interface in this area is 3 Area has no authentication SPF algorithm last executed 00:08:00.000 ago SPF algorithm executed 6 times Network Three Routers(R1, R2, R3) R1 is connected to R2 via Serial link(R1: S0/0/0, R2:S0/0/0, Network: 172.20.1.0/30) R1 is connected to R3 via Serial link(R1: S0/0/1, R3: S0/0/1, Network: 172.20.1.4/30) R2 is connected to R3 via Serial link(R2: S0/0/1, R3: S0/0/0, Network: 172.20.1.8/30) R1 has network 192.168.1.0/24 attached to the Fa0/0 interface R2 has network 192.168.2.0/24 attached to the Fa0/0 interface R3 has network 192.168.3.0/24 attached to the Fa0/0 interface 1. This router is a border router between Area 0 and Area 1 2. Other routers must authenticate with this router to form an adjacency. 3. No topology changes involving this router have taken place in the last 24 hours 4. This router has 3 OSPF interfaces that are up. 5. The ospf process ID for this router is 192.168.1.1 Scenario 3 R1#show ip ospf interface FastEthernet0/0 is up, line protocol is up Internet Address 192.168.1.1/24, Area 0 Process ID 1, Router ID 192.168.1.1, Network Type BROADCAST, Cost: 1 Transit Delay is 1 sec, State DR, Priority 1 Designated Router (ID) 192.168.1.1, Interface address 192.168.1.1 No Backup Designated router on this network Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Neighbor Count is 0, Adjacent neighbor count is 0 Serial0/0/1 is up, line protocol is up Internet Address 172.20.1.1/30, Area 0 Process ID 1, RouterID 192.168.1.1, Network Type POINT_To_POINT,Cost:64 Timerintervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Neighbor Count is 1, Adjacent neighbor count is 1 Three Routers(R1, R2, R3) R1 is connected to R2 via Serial link(R1: S0/0/0, R2:S0/0/0, Network: 172.20.1.0/30) R1 is connected to R3 via Serial link(R1: S0/0/1, R3: S0/0/1, Network: 172.20.1.4/30) R2 is connected to R3 via Serial link(R2: S0/0/1, R3: S0/0/0, Network: 172.20.1.8/30) R1 has network 192.168.1.0/24 attached to the Fa0/0 interface R2 has network 192.168.2.0/24 attached to the Fa0/0 interface R3 has network 192.168.3.0/24 attached to the Fa0/0 interface 1. This router has 3 OSPF interfaces 2. This router is a Designated Router (DR) for the 192.168.1.0 network 3. Link S0/0/1 is point-to-point with a cost 64 indicating it is a T1 4. The OSPF network type for interface S0/90/0 is Broadcast 5. This router has only one adjacent neighbor Scenario 4 R1#show ip route Gateway of last resort is not set 172.20.0.0/30 is subnetted, 3 subnets O 172.20.1.8 [110/128] via 172.20.1.6, 00:02:55, Serial0/0/1 [110/128] via 172.20.1.2, 00:02:55, Serial0/0/0 O 172.20.1.0 is directly connected, Serial0/0/0 O 172.20.1.4 is directly connected, Serial0/0/1 O 192.168.1.0/24 is directly connected, FastEthernet0/0 O 192.168.2.0/24 [110/65] via 172.20.1.2, 00:02:55, Serial0/0/0 O 192.168.3.0/24 [110/65] via 172.20.1.6, 00:02:55, Serial0/0/1 Network Three Routers(R1, R2, R3) R1 is connected to R2 via Serial link(R1: S0/0/0, R2:S0/0/0, Network: 172.20.1.0/30) R1 is connected to R3 via Serial link(R1: S0/0/1, R3: S0/0/1, Network: 172.20.1.4/30) R2 is connected to R3 via Serial link(R2: S0/0/1, R3: S0/0/0, Network: 172.20.1.8/30) R1 has network 192.168.1.0/24 attached to the Fa0/0 interface R2 has network 192.168.2.0/24 attached to the Fa0/0 interface R3 has network 192.168.3.0/24 attached to the Fa0/0 interface 1. There are two equal-cost routes to the 172.20.1.8 network from this router 2. The OSPF cost of the route to the 192.168.3.0 network is 128 3. The IP address for the next hop interface for network 192.168.2.0 is 172.20.1.6 4. Router R1 receives updates from R3 on FastEthernet 0/0 5. This router learned about network 192.168.3.0 from R3 Scenario 5 R1#debug ip ospf packet OSPF packet debugging is on R1# *Sep 14 17:26:36.475: OSPF: rcv. V:2 t:1 1:48 rid:192.168.2.1 aid:0.0.0.0 chk:674B aut:0 auk: from Serial0/0/0 *Sep 14 17:26:40.651: OSPF: rcv. V:2 t:1 1:48 rid:192.168.3.1 aid:0.0.0.0 chk:664B aut:0 auk: from Serial0/0/1 *Sep 14 17:26:46.475: OSPF: rcv. V:2 t:1 1:48 rid:192.168.2.1 aid:0.0.0.0 chk:674B aut:0 auk: from Serial0/0/0 *Sep 14 17:26:50.651: OSPF: rcv. V:2 t:1 1:48 rid:192.168.3.1 aid:0.0.0.0 chk:664B aut:0 auk: from Serial0/0/1 Network Three Routers(R1, R2, R3) R1 is connected to R2 via Serial link(R1: S0/0/0, R2:S0/0/0, Network: 172.20.1.0/30) R1 is connected to R3 via Serial link(R1: S0/0/1, R3: S0/0/1, Network: 172.20.1.4/30) R2 is connected to R3 via Serial link(R2: S0/0/1, R3: S0/0/0, Network: 172.20.1.8/30) R1 has network 192.168.1.0/24 attached to the Fa0/0 interface R2 has network 192.168.2.0/24 attached to the Fa0/0 interface R3 has network 192.168.3.0/24 attached to the Fa0/0 interface 1. The router is receiving OSPF version 2 packets 2. The router is receiving OSPF packets from two other routers 3. The packet type being received is Hello packets 4. MD5 authentication is being used on this router 5. This router is receiving packets from R2 on S0/0/1 Diagram 3, Hands on Lab 9.3.4 ? Route Redistribution Issues Diagram 1, Image The picture depicts a network, and shows screen captures of some of the various commands used for RIP, EIGRP, OSPF. The key/highlighted parts include: Network Three Routers(R1, R2, ISP) R1 is connected to R2 via Serial link (R1: S0/0/0, R2: S0/0/0, Network: 172.20.1.0/30) R2 is connected to ISP via Serial link (R2: S0/0/1, ISP: S0/0/0, Network: 209.165.2200.224/30) R1 has network 192.168.1.0/24 attached on the Fa0/0 interface R2 has network 192.168.2.0/24 attached on the Fa0/0 interface ISP has network 10.1.1.0/24 attached on Lo0 RIP R2#Show running-config R2#Show ip route Gateway of last resort is 209.165.200.226 to network 0.0.0.0 S* 0.0.0.0/0 [1/0] via 209.165.200.226 Diagram 2, Lab Activity Route Redistribution Issues EIGRP R1#show ip route Gateway of last resort is 209.165.200.226 to network 0.0.0.0 S* 0.0.0.0/0 [1/0] via 209.165.200.226 R2#show running-config OSPF R2#show running-config R2#show ip route Gateway of last resort is 209.165.200.226 to network 0.0.0.0 S* 0.0.0.0/0 [1/0] via 209.165.200.226 Diagram 3, Hands on Lab 9.4.1 - Troubleshooting WAN Connectivity Five Diagrams Diagram 1, Image R1, DCE connects to R2, DTE. The show controllers command is issued on the R1 router and the following line is highlighted in the show command output DCE V.35, clock rate 56000. The show controllers command is issued on the R2 router and the following line is highlighted in the show command output DTE V.35 TX and RX clocks detected. Diagram 2, Image R1, DCE connects to R2, DTE. The show interfaces command is issued on the R1 router and the following line is highlighted in the show interfaces output Encapsulation PPP. The show interfaces command is issued on the R2 router and the following line is highlighted in the show interfaces output Encapsulation PPP. Diagram 3, Image Switch S1 is connected to switch S2. Switch S2 is connected to the Fa0/0 of router R1. R1 connects to the WAN via its S0/0/1 port. The following is the output the show ip interface brief command. R1#show ip interface brief Interface IP-Address OK? Method Status Protocol FastEthernet0/0 unassigned Yes manual up up FastEthernet0/0.100 10.20.100.1 Yes manual up up FastEthernet0/0.101 10.20.101.1 Yes manual up up FastEthernet0/0.102 10.20.102.1 Yes manual up up FastEthernet0/0.103 10.20.103.1 Yes manual up up Serial0/0/0 unassigned YES manual up up FastEthernet0/1 unassigned YES unset administratively down down Serial0/0/1 10.20.30.1 YES manual up up Diagram 4, Image Router R1 is connected to Router R2 via a serial connection. When the show interfaces s0/0/1 command is issued on router 1 the encapsulation PPP, LCP Open and Open: IPCP, CDPCP lines are highlighted. When the debug ppp negotiation command is issued on R1 the following output is highlighted: 1d05h: Se0/0/1 LCP: AuthProto CHAP (0x0305c22305) 1d05h: Se0/0/1 LCP: Lower layer not up, Fast Starting 1d05h: Se0/0/1 PPP: Treating connection as dedicated line 1d05h: Se0/0/1 PPP: Phase is ESTABLISHING, Active Open 1d05h: Se0/0/1 LCP: AuthProto CHAP (0x0305c22305) 1d05h: Se0/0/1 LCP: State is Open 1d05h: Se0/0/1 PPP: Phase is AUTHENTICATING, by both 1d05h: Se0/0/1 CHAP: O CHALLENGE id 146 len 28 from ?R1? 1d05h: Se0/0/1 CHAP: I CHALLENGE id 148 len 27 from ?R2? 1d05h: Se0/0/1 CHAP: Using hostname from configured hostname 1d05h: Se0/0/1 CHAP: O CHALLENGE id 146 len 28 from ?R1? 1d05h: Se0/0/1 CHAP: Using password from AAA 1d05h: Se0/0/1 CHAP: O RESPONSE id 146 len 28 from ?R1? 1d05h: Se0/0/1 CHAP: I RESPONSE id 148 len 27 from ?R2? 1d05h: Se0/0/1 PPP: Phase is AUTHENTICATING, Unauthenticated User 1d05h: Se0/0/1 CHAP: I SUCCESS id 148 len 4 1d05h: Se0/0/1 PPP: Phase is AUTHENTICATING, Unauthenticated User 1d05h: Se0/0/1 CHAP: O SUCCESS id 146 4 1d05h: Se0/0/1 PPP: Phase is up 1d05h: Se0/0/1 IPCP: State is Open 1d05h: Se0/0/1 CDCP: State is Open 1d05h: %LINEPRONTO-5-UPDOWN: Line protocol on Interface Serial0/0/1, changed state to up When the debug ppp packet command is issued on R1 the following output is highlighted: R1#debug ppp packet PPP packet diplay debugging is on R1# 1d05h: Se0/0/1 LCP: O ECHOREQ [Open] id 1 len 12 magic 0x136F1E39 1d05h: Se0/0/1 PPP: I pkt type 0xC021, datagramsize 16 1d05h: Se0/0/1 LCP: I ECHOREQ [Open] id 1 len 12 magic 0x13663C01 1d05h: Se0/0/1 LCP: Received is 1, sent id 1, line up 1d05h: Se0/0/1 PPP: I pkt type 0xC021, datagramsize 16 1d05h: Se0/0/1 LCP: I ECHOREQ [Open] id 1 len 12 magic 0x13663C01 1d05h: Se0/0/1 LCP: O ECHOREQ [Open] id 1 len 12 magic 0x136F1E39 1d05h: Se0/0/1 PPP: 0 pkt type 0x0021, datagramsize 116 1d05h: Se0/0/1 LCP: O ECHOREQ [Open] id 2 len 12 magic 0x136F1E39 1d05h: Se0/0/1 PPP: I pkt type 0xC021, datagramsize 16 1d05h: Se0/0/1 LCP: I ECHOREQ [Open] id 2 len 12 magic 0x13663C01 1d05h: Se0/0/1 LCP: Received id 2, sent id 2, line up 1d05h: Se0/0/1 PPP: I pkt type 0xC021, datagramsize 16 1d05h: Se0/0/1 LCP: I ECHOREQ [Open] id 2 len 12 magic 0x13663C01 1d05h: Se0/0/1 LCP: O ECHOREQ [Open] id 2 len 12 magic 0x136F1E39 1d05h: Se0/0/1 LCP: O ECHOREQ [Open] id 3 len 12 magic 0x136F1E39 1d05h: Se0/0/1 PPP: I pkt type 0xC021, datagramsize 16 1d05h: Se0/0/1 LCP: I ECHOREQ [Open] id 3 len 12 magic 0x13663C01 1d05h: Se0/0/1 LCP: Received id 3, sent id 3, line up 1d05h: Se0/0/1 PPP: I pkt type 0xC021, datagramsize 16 1d05h: Se0/0/1 LCP: I ECHOREQ [Open] id 3 len 12 magic 0x13663C01 1d05h: Se0/0/1 LCP: O ECHOREQ [Open] id 3 len 12 magic 0x136F1E39 show interfaces s0/0/1 The information below is highlighted Encapsulation PPP LCP Open Open: IPCP, CDPCP Diagram 5, Packet Tracer Exploration 9.4.2 - Troubleshooting WAN Authentication Four Diagrams Diagram 1, Image The four steps used when debugging PPP. Step 1 Identify the problem. Man sitting at a host connected to a simple network thinks ?I cannot connect to R2.? Step 2 Use the debug PPP negotiation command. Step 3 Use the debug PPP authentication command. Step 4 Once the problem has been identified implement a solution. Man thinks ?I see the error, i will change the R2 to CHAP and try again.? Diagram 2, Image R1 is connected via a serial connection to R2. Proper Configuration The following lines should be outputted as a result of a proper configuration. 03:03:35: Se0/0/1 PPP: Received LOGIN Response from AAA = PASS 03:03:36: %LINEPRONTO-5-UPDOWN: Line protocol on Interface Serial0/0/1, changes state to up No User Account The following line should be outputted as a result of no user account. 03:21:43: SE0/0/1 CHAP: Unable to authenticate for peer Wrong Password The following line should be outputted as a result of a wrong password. 03:17:47: SE0/0/1 PPP: Received LOGIN Response from AAA = FAIL Diagram 3, Packet Tracer Exercise Diagram 4, Activity, Hands-on Lab 9.5 ? Troubleshooting ACL Issues 9.5.1 ? Determining if an ACL is the Issue 4 Diagrams Diagram 1, Image The image depicts two hosts connected to a switch. The two hosts have the IP addresses 192.168.1.2 and 192.168.1.3 and are part of the 192.168.1.0/24 network. The switch is connected to the router R1 Fa0/0. This interface has an ACL applied (ACL 123 inbound). R1 S0/0 is connected to router R2, network address 172.20.0.1/30. R2 Fa0/0 is connected to another switch, on 192.168.2.0/24 and there is a server connected to the switch with an IP address of 192.168.2.2. The configuration commands for placing the ACL are listed below: R1(config)# access-list 123 deny tcp host 192.168.1.2 host 192.168.2.2 eq 23 log R1(config)# access-list 123 permit ip 192.168.1.0 0.0.0.255 any log R1(config)# access-list 123 deny ip any any log R1(config)# int fa0/0 R1(config-if)# ip access-group 123 in ACL Console Logging *Sep 12:34:35:54.067: *SEC ? 6 ?IPACCESSLOGP: list 123 denied tcp 192.168.1.2(1141)-->192.168.2.2(23), 1 packet R1# * Sep 12:34:35:54.067: *SEC ? 6 ?IPACCESSLOGP: list 123 permitted icmp 192.168.1.3--> 192.168.2.2 (8/0), 1 packet Diagram 2, Image The image depicts two hosts connected to a switch. The two hosts have the IP addresses 192.168.1.2 and 192.168.1.3 and are part of the 192.168.1.0/24 network. The switch is connected to the router R1 Fa0/0. This interface has an ACL applied (ACL 123 inbound). R1 S0/0 is connected to router R2, network address 172.20.0.1/30. R2 Fa0/0 is connected to another switch, on 192.168.2.0/24 and there is a server connected to the switch with an IP address of 192.168.2.2. The commands listed in the image are as follows with the highlighted output included: R1# show running-config: IP address 192.168.1.1 255.255.255.0 IP access-group 123 in Output omitted Access-list 123 deny tcp host 192.168.1.2. host 192.168.2.2 eq telnet Access-list 123 permit ip 192.168.1.0 0.0.0.255 any R1# debug ip packet *Sep 19 ?omitted? IP: s=192.168.1.2(fastethernet0/0), d=192.168.2.2, len 48, access denied R1# show ip interface Outgoing access list is not set Inbound access list is 123 R1# show access-lists Displays the number of matches to the ACLs (examine in lab) Diagram 3, Activity Analyze the network topology and router command output. Indicate whether the statements regarding ACL?s and their effects are true or false. For each scenario, select True or False for the series of statements. Topology: The image depicts two hosts connected to a switch. The two hosts have the IP addresses 192.168.1.2 and 192.168.1.3 and are part of the 192.168.1.0/24 network. The switch is connected to the router R1 Fa0/0. This interface has an ACL applied (ACL 123 inbound). R1 S0/0 is connected to router R2, network address 172.20.0.1/30. R2 Fa0/0 is connected to another switch, on 192.168.2.0/24 and there is a server connected to the switch with an IP address of 192.168.2.2. Scenario 1 The router output for the command ?show running-config? is listed below: R1# show running-config Bullding Configuration?. (**output omitted**) Hostname R1 Interface Fast Ethernet 0/0 Description LAN gateway for 192.168.1.0 ent Ip address 192.168.1.1 255.255.255.0 Ip access-group 123 in Duplex auto Speed auto Interface FastEthernet 0/1 No ip address Shutdown Duplex auto Speed auto Interface Serial0/0/0 Description WAN link to R2 Ip address 172.20.1.1 255.255.255.252 No fair-queue Interface Serial0/0/1 No ip address Shutdown Router RIP Version 2 Passive-interface FastEthernet 0/0 Network 172.20.0.0 Network 192.168.1.0 No auto-summary Access-list 123 permit tcp host 102.168.1.2 any eq telnet Access-list 123 permit tcp host 192.168.1.2 any range ftp-data ftp Access-list 123 deny tcp any any eq telnet Access-list 123 tcp any any range ftp-date ftp Access-list 123 permit ip 192.168.1.0 0.0.0.255 any Access-list 123 deny ip any any Statements. 1. This router is configured with a standard ACL ? True or False 2. If a telnet packet from 192.168.1.5 enters Fa0/0 it will be permitted. 3. Host 192.168.1.2 is permitted to transfer files to and from any FTP server. 4. This ACL is applied to Fa0/0 inbound. 5. If an HTTP packet from a host on network 192.168.1.0 is received on Fa0/0 inbound it will permitted. Scenario 2. The router output for the command ?show access-list? is listed below: R1#show access-list Extended IP access-list 123 Permit tcp host 192.168.1.2 any eq telnet (24 matches) Permit tcp host 192.168.1.2 any range ftp-data ftp Deny tcp any any eq telnet (8 matches) Permit ip 192.168.1.0 0.0.0.255 any (250 matches) Deny ip any any (22 matches) Statements 1. This router ACL allows an administrator PC (192.168.1.2) to Telnet and FTP to any location. 2. The administrator has been using FTP extensively 3. PC?s other than 192.168.1.2 on the 192.168.1.0 network have attempted to telnet to other networks. 4. This ACL prevents transferring a file using using FTP from PC 192.168.1.3 to PC 192.168.1.5 5. Most hosts have used ip protocols other than FTP and telnet (eg. HTTP) to connect to other networks. Scenario 3 The router output for the command ?debug ip packet? is listed below: R1# debug ip packet IP packet debugging is on R1# *Sep 19 17:09:25.555: IP: s=192.168.1.3 (Fast Ethernet 0/0), d=192.168.2.2, len 48, access denied *Sep 19 17:09:26.555: IP: tableid=0, s=192.168.1.1 (local), d=192.168.1.3 (FastEthernet 0/0) routed via FIB *Sep 19 17:11:34:555: IP: s=172.20.1.2 (Serial 0/0/0), d= 224.0.0.9, len 52, recvd *Sep 19 17:11:45.119: IP: s=172.20.1.1 (local), d=224.0.0.9 (Serial0/0/0), len 52, sending broadcast/multicast R1# Statements 1. All packets from host 192.168.1.5 have been permitted by this router and ACL. 2. This router is running only the EIGRP routing protocol. 3. Packets from host 192.168.1.3 may be permitted by this router and ACL depending on the protocol they are using. 4. Routing updates to multicast addresses 224.0.0.9 are being blocked by the ACL on this router. 5. The IP address of the S0/0/0 interface on this router is 172.20.1.2 Diagram 4, Packet Tracer Exercise 9.5.2 ? ACL Configuration and Placement Four Diagrams Diagram 1, Image The image depicts two hosts directly connected to a switch. The two hosts have the IP addresses 192.168.1.2 and 192.168.1.3 and are part of the 192.168.1.0/24 network. The switch is connected to the router R1. Router R1 S0/0/0 is connected router R2 s0/0/0, 172.20.1.0/30. An ACL (123) has been placed on the serial interface S0/0/0 inbound on R2. R2 Fa0/0 is connected to another switch 192.168.2.0/24 and a server connected to the switch with an IP address of 192.168.2.2. The outputs for the commands listed below can be viewed in the labs once protocols and interfaces have been configured on both routers R1 and R2. - R1# show ip route - R1# debug ip rip - R2# show ip route - R2# (console logging on) - R2# debug ip rip - R2# show access-lists - R2# show ip interface s0/0/0 Diagram 2, Image The diagram depicts four routers connected by serial links to each other. The routers have been named R1, R2, R3 and R4. On router R1 there is an extended ACL placed on Fa0/0 which connects network 192.168.1.0/24 to router R1. The extended ACL information is as follows: Extended ACL - Place closest to source - Denies traffic from 192.168.1.0 network from reaching 192.168.4.0 - Allows it to reach other networks and saves bandwidth ACL commands Access-list 101 deny ip 192.168.1.0 0.0.0.255 192.168.4.0 0.0.0.255 access-list 101 permit ip any any Router R2 connected to network 192.168.2.0/24 and is also connected to R4. Router R3 connects to both R1 and R4. R3 is connected to network 192.168.3.0/24. Router R4 has its Fast Ethernet Fa0/0 OUT in use and connected to network 192.168.4.0/24 and there is a Standard ACL placed between the 192.168.4.0/24 network and the interface. The Standard ACL information is as follows: Standard ACL - Place closest to the destination - Denies 192.168.1.0 traffic to 192.168.4.0 - Wastes bandwidth ACL commands Access-list 1 deny 192.168.1.0 0.0.0.255 Access-list 1 permit any Diagram 3, Packet Tracer Exercise Diagram 4, Hands On Lab Module 9.6 ? Chapter Summary 9.6.1 Summary One Diagram Diagram 1, Tabular Slide 1 Adherence to the three-layer hierarchical network design model assists in troubleshooting efforts. Network monitoring tools include: network utilities, packet sniffing tools and SNMP monitoring tools. SNMP enables monitoring the performance of individual devices on the network using agents and a MIB. Backups of the configuration files, spare devices, or backup sites enable quick restoration of connectivity. The business continuity plan details the security policy and disaster recovery plan. When troubleshooting a network, determine the scope of the problem and isolate the issue to a specific failure domain. Slide 2 The most common problems with switches occur at the Physical Layer. Visually checking LEDs and cable connections assist in troubleshooting Physical Layer problems. Change the priority value on a switch to force the selection of the root bridge. The route bridge should be centrally located within the network. Ensure there are two VTP servers in one domain to provide backup. Ensure all devices sharing VLAN information have the same VTP domain name. Check the VTP revision information and mode before enabling a switch to join the network. Slide 3 Many tools exist for troubleshooting routing issues include IOS show commands, debug commands and TCP/IP utilities. Use debug commands to isolate problems, not to monitor normal network operation. Problems with RIPv1 include lack of VLSM support and intermixing RIPv1 and RIPv2 devices. Common issues with EIGRP include: mismatched AS numbers, incorrect wildcard mask, and auto-summarization issues with discontiguous subnets. The majority of OSPF problems relate to the formation of adjacencies and the synchronization of the link-state databases. Slide 4 The most common physical layer WAN problems are not specifying a clock rate on the link or using the wrong type of cable. SLARP assigns an IP address to the end point of a serial link if the other end is already configured. Ensure that the encapsulation is the same on both sides of the serial link. If an IP address is used both ends of the link must be on the same network or subnet. When troubleshooting PPP connectivity verify that the LCP has been opened, authentication and NCP completed. For enhanced security, use mutual authentication. On both ends of the link, verify that a user account exists for the remote device and that the password is correct. By default, the username used during the authentication process is the name of the remote router. Both the username and the password are case sensitive. Slide 5 ACLs can create complications in troubleshooting network issues. Always verify basic network connectivity before applying an ACL. Enable logging to determine the effect that ACLs have on traffic. ACL needs to be applied to the correct router and interface and in the correct direction. Standard ACLs filter only on one source IP address so they are normally placed as close to the destination as possible. An Extended ACL filters on source and destination as well as protocols and port numbers. Placing an extended ACL close to a source can deny traffic before it passes though the router and before it traverses the WAN link. An ACL placed on the wrong interface or in the wrong direction can block traffic that should not be blocked or permit traffic that should not be permitted. 9.6.2 ? Critical Thinking One Diagram Diagram 1, Activity Critical Thinking Answer the following questions based on the exhibit. Exhibit Network Two Routers(R2, R3) Two Switches(S1, S2) R2 is connected to R3 via serial link(network: 192.168.16.0/30) R2 has S1 attached(network: 10.10.4.0/24) R3 has S2 attached(network: 10.10.3.0/24) S1 has one host attached (Host IP: 10.10.4.63/24) S2 has one host attached (Host IP: 10.10.3.75/24) There is a screen capture of a R2?s command Prompt, which is as follows: Hostname R2 interface fa0/0 ip address 10.10.4.1 255.255.255.0 interface s0/0 ip address 192.168.16.1 255.25.255.252 ! router rip network 192.168.16.0 network 10.0.0.0 1. Which route advertisements does R3 receive from R2? 1. 10.0.0.0/24 2. 10.10.4.0/24 3. 10.0.0.0/8 4. 10.0.0.0/8 and 10.10.4.0/24 5. 10.0.0.8, 10.0.0.0/24 and 10.10.4.0/24 2. If host 10.10.3.75 attempts to ping host 10.10.4.63, what will the results be? 1. All packets will be dropped. 2. Some packets will be dropped. 3. All packets will reach the destination and network applications will have connectivity. 4. All packets will reach the destination but network applications will not have connectivity. 3. What must an administrator do on R3 to ensure that update packets are sent with subnet mask information? 1. Add the command: R2(config-router)#no version 2 2. Add the command: R3(config-router)# version 2, R3(config-router)#no auto-summary 3. Change the network statement on Router 3: R3(config)#network 10.10.4.0 4. Add the command: R3(config)#ip route 0.0.0.0 0.0.0.0 s0/0 4. Router R1 and R3 is configured with the commands: version 2 no auto-summary Which two statements are true? (Choose two.) 1. A ping command will be successful between host 19.100.3.75 and host 10.10.4.63. 2. Router R2 is able to send and receive RIPv1 and RIPv2 update packets. 3. Router R2 is able to receive RIPv1 and RIPv2 update packets. 4. A ping command will fail between host 10.10.3.75 and h