By default, the broadcast ping will be terminated by R1 but it will itself respond to the ping. By configuring R1 with the command ip directed-broadcast on Fast Ethernet0/0, R1 will then forward the ping to the whole destination subnet, which will result in R6, R8, and Switch1 also replying to the ping. Example 2-72 shows verification of a broadcast ping to 10.80.80.255 initiated from R3 with replies received from R1, R6, R8, and Switch1. If you have configured this correctly, you have scored 3 points. Example 2-72. R3 Broadcast Ping VerificationR3#debug ip icmp ICMP packet debugging is on R3#ping 10.80.80.255 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.80.80.255, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/8 ms R3# 01:35:39: ICMP: echo reply rcvd, src 10.90.90.2, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.90.90.2, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.2, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.3, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.2, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.8, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.3, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.90.90.2, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.2, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.8, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.3, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.90.90.2, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.2, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.8, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.3, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.90.90.2, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.2, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.8, dst 172.16.0.2 01:35:39: ICMP: echo reply rcvd, src 10.80.80.3, dst 172.16.0.2
You need to configure LAM on R6 with an access group that only permits host 10.50.50.2. You have to redistribute mobile into OSPF on R6 so your network learns where host 10.50.50.2 is by the more specific host route that R6 will generate. R7 will now be able to communicate only with its home subnet VLAN4. Remember that R7 does not have routing capability at this point. If you have configured this correctly as shown in Example 2-73, you have scored 4 points. Example 2-73. R6 LAM Configuration and Verificationinterface FastEthernet4/0 ip address 10.60.60.1 255.255.255.248 ip mobile arp access-group 50 ! router ospf 30 redistribute mobile subnets default-metric 4000 ! access-list 50 permit 10.50.50.2 R7#ping 10.50.50.1 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.50.50.1, timeout is 2 seconds: .!!!! Success rate is 80 percent (4/5), round-trip min/avg/max = 1/3/4 ms
As mentioned in the previous question, R7 does not have routing capability so you will have to manipulate the router to perform this connectivity. As you cannot use any form of routing to achieve this, you must forward the traffic for the destinations to R6, which has full visibility of the entire network. If you look at the ARP cache of R7, you will find that it already has an ARP entry for 10.50.50.1, which is, in fact, that of R6. Setting up static ARP entries in R7 for the remote destinations pointing to the MAC address of R6 should do the trick; however, it actually requires one further piece of configuration to make this work. As the remote networks are all in different IP subnets to that of R7 Fast Ethernet0/0, the static mappings will not work. By adding a secondary address on R7, which covers all subnets (that is, 10.0.0.1/8), you will find you now have full connectivity to the remote destinations. If you have configured this correctly as shown in Example 2-74 you have scored 5 points. Example 2-75, shows R7 ARP table and ping test results. Example 2-74. R7 LAM Configurationinterface FastEthernet0/0 ip address 10.0.0.1 255.0.0.0 secondary ip address 10.50.50.2 255.255.255.248 speed 100 full-duplex ! arp 10.8.8.8 0001.9799.9870 ARPA arp 10.1.1.1 0001.9799.9870 ARPA arp 10.6.6.6 0001.9799.9870 ARPA arp 10.4.4.4 0001.9799.9870 ARPA arp 10.5.5.5 0001.9799.9870 ARPA Example 2-75. R7 LAM TestingR7#sh arp Protocol Address Age (min) Hardware Addr Type Interface Internet 10.8.8.8 - 0001.9799.9870 ARPA Internet 10.50.50.2 - 0008.a3d1.9c20 ARPA FastEthernet0/0 Internet 10.50.50.1 0 0001.9799.9870 ARPA FastEthernet0/0 Internet 10.0.0.1 - 0008.a3d1.9c20 ARPA FastEthernet0/0 Internet 10.1.1.1 - 0001.9799.9870 ARPA Internet 10.6.6.6 - 0001.9799.9870 ARPA Internet 10.4.4.4 - 0001.9799.9870 ARPA Internet 10.5.5.5 - 0001.9799.9870 ARPA R7# R7#ping 10.1.1.1 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.1.1.1, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 8/8/8 ms R7#ping 10.4.4.4 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.4.4.4, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/8 ms R7#ping 10.5.5.5 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.5.5.5, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/4 ms R7#ping 10.6.6.6 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.6.6.6, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/4 ms R7#ping 10.8.8.8 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.8.8.8, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms R7#ping 10.50.50.1 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.50.50.1, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/3/4 ms
Before R4 would be able to load share for this future advertisement, you must ensure that the metrics for the route are exactly the same. As the network is to be advertised within OSPF and not redistributed with a default-metric cost, the network will be assigned a metric according to the assigned bandwidth statements on the Frame Relay PVCs. As you cannot change the bandwidth statements, you simply adjust the costs on the R4 interfaces to the same value for each PVC. If you have configured this correctly as in Example 2-76, you have scored 2 points. You will not be deducted points if you have not disabled the route caching feature, which is enabled by default. Example 2-76. R4 Future Load Sharing Configurationinterface Virtual-Template1 bandwidth 256 ip ospf cost 400 ! interface Virtual-Template2 bandwidth 512 ip ospf cost 400 |