capitulo 8 cisco ccna 1

capitulo 8 cisco ccna 1.2. Troubleshooting OSPF InterfacesOSPF has the same basic requirements for interfaces as EIGRP, but there are exceptions. First, EIGRP routers need to use the same autonomous system number (ASN) as their neighboring routers, which is configured using the router eigrp asn global command. However, OSPF routers can use any process ID, and do not need to match their neighbors. Second, OSPF requires that interfaces connected to the same subnet be assigned to the same OSPF domain, whereas EIGRP does not have the concept of zones.Example 11-5 shows a mostly functioning OSPF interconnection network, again based on Figure ll-3o The problem in that case affects the area design as shown in Figure 11-4. This figure is a modified version of Figure II. all subnets in the figure should be located in area 0. However, the administrator made a misconfiguration on R2 and mistakenly configured two interfaces on it to be within areal. The result is that R2's G0/0 interface breaks the OSPF design rule because it Rl, R2, and R4 are in the same subnet but not in the same OSPF area.Expected design: area 0 only Figure 11-4 For designs corrupted by R2, use only area 0 preset area design10.1.33.3/24 Example 11-5 First, execute the showip ospfinterface brief command, through which you observe the state of OSPF on router R1 and R2 interfacesExample 11-5 G0/1Rl> show ip ospf interface brief 10.1.44.4/24Interface PID Area IP Address/Mask Cost State Nbrs F/CGiO/1 1 10.1.11.1/24 1 DR 0/0Gi0/0 Recipient, 1 o 10.1.1.1/24 1 DROTH 2/2