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A network engineer is troubleshooting OSPF adjacency issues between two routers connected via a Gigabit Ethernet link. The engineer notices that the routers are stuck in the EXSTART state. Both routers have the same MTU of 1500 bytes. What is the most likely cause of this issue?
2An enterprise network uses OSPF as its IGP. The network engineer notices that a particular route learned via OSPF is not being installed in the routing table, even though the neighbor adjacency is up and the route appears in the OSPF database. The route is an external route redistributed from EIGRP. What is the most likely cause?
3A network engineer is configuring OSPF in a multi-area design. The engineer wants to reduce the amount of LSA flooding and the size of the LSDB in area 0. Which OSPF feature should be implemented on the ABR to achieve this goal?
4A network engineer is troubleshooting an OSPF adjacency issue between two routers connected via a serial link. The adjacency is stuck in the INIT state. The engineer has verified that the IP addresses are in the same subnet and that the link is up. What is the most likely cause?
5A network engineer is designing an OSPF network with multiple areas. The engineer wants to ensure that routers in area 2 can reach networks in area 0, but they should not learn any external routes from other ASs. Which OSPF area type should be configured for area 2?
6A network engineer is troubleshooting an OSPF issue where a router is not learning a route to a network that is advertised via a type 5 LSA from an ASBR. The engineer checks the OSPF database and sees the type 5 LSA, but the route is not in the routing table. The forwarding address in the LSA is 0.0.0.0. What is the most likely cause?
7A network engineer is configuring OSPF on a router that connects to two different ISPs. The engineer wants to prefer one ISP for all external routes unless that ISP's link fails, in which case the other ISP should be used. Which OSPF feature should be used to influence the path selection for external routes?
8A network engineer is troubleshooting an OSPF adjacency issue between two routers connected via a Frame Relay network. The adjacency is stuck in the 2WAY state. The engineer has verified that the routers are in the same area and have matching hello/dead intervals. What is the most likely cause?
9A network engineer is configuring OSPF on a router that has multiple interfaces in the same area. The engineer wants to ensure that the router does not become the designated router (DR) on any of these interfaces. What should the engineer do?
10A network engineer runs the following command on Router R1: R1# show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 10.0.0.2 1 FULL/DR 00:00:32 192.168.1.2 GigabitEthernet0/0 10.0.0.3 1 2WAY/DROTHER 00:00:35 192.168.1.3 GigabitEthernet0/0 Based on this output, what can be concluded?
11A network engineer issues the following command on Router R2: R2# show ip ospf interface GigabitEthernet0/0 GigabitEthernet0/0 is up, line protocol is up Internet Address 192.168.1.2/24, Area 0 Process ID 1, Router ID 2.2.2.2, Network Type BROADCAST, Cost: 10 Transmit Delay is 1 sec, State DR, Priority 1 Designated Router (ID) 2.2.2.2, Interface address 192.168.1.2 Backup Designated router (ID) 1.1.1.1, Interface address 192.168.1.1 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:03 Index 1/1/1, flood queue length 0 Next 0x0(0)/0x0(0)/0x0(0) Last flood scan length is 1, maximum is 1 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 2, Adjacent neighbor count is 2 Adjacent with neighbor 1.1.1.1 (Backup Designated Router) Adjacent with neighbor 3.3.3.3 Based on this output, what can be concluded?
12A network engineer runs the following command on Router R3: R3# show ip route ospf Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2 i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2 ia - IS-IS inter area, * - candidate default, U - per-user static route o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP a - application route + - replicated route, % - next hop override Gateway of last resort is not set 10.0.0.0/8 is variably subnetted, 5 subnets, 3 masks O IA 10.1.1.0/24 [110/20] via 192.168.1.1, 00:12:34, GigabitEthernet0/0 O 10.2.2.0/24 [110/10] via 192.168.1.2, 00:15:22, GigabitEthernet0/0 O E2 10.3.3.0/24 [110/20] via 192.168.1.3, 00:08:11, GigabitEthernet0/0 Based on this output, what can be concluded?
13A network engineer issues the following command on Router R4: R4# show ip ospf database OSPF Router with ID (4.4.4.4) (Process ID 1) Router Link States (Area 0) Link ID ADV Router Age Seq# Checksum Link count 1.1.1.1 1.1.1.1 123 0x80000002 0x00A1B2 2 2.2.2.2 2.2.2.2 456 0x80000003 0x00B2C3 3 4.4.4.4 4.4.4.4 789 0x80000001 0x00C3D4 1 Net Link States (Area 0) Link ID ADV Router Age Seq# Checksum 192.168.1.2 2.2.2.2 234 0x80000001 0x00D4E5 Based on this output, what can be concluded?
14A network engineer runs the following command on Router R5: R5# show ip ospf border-routers OSPF Process 1 internal Routing Table Codes: i - Intra-area route, I - Inter-area route i 1.1.1.1 [110/10] via 192.168.1.1, GigabitEthernet0/0, ABR, Area 0, SPF 5 i 2.2.2.2 [110/20] via 192.168.1.2, GigabitEthernet0/0, ASBR, Area 0, SPF 5 Based on this output, what can be concluded?
15A network engineer issues the following command on Router R6: R6# debug ip ospf hello OSPF: Send hello to 224.0.0.5 via GigabitEthernet0/0 (192.168.1.6) OSPF: Rcv hello from 1.1.1.1, GigabitEthernet0/0, area 0.0.0.0 Neighbor state is 2WAY, options 0x2 OSPF: End of hello processing Based on this output, what can be concluded?
16A network engineer runs the following command on Router R7: R7# show ip ospf virtual-links Virtual Link OSPF_VL0 to router 2.2.2.2 is up Run as demand circuit DoNotAge LSA allowed. Transit area 1, via interface GigabitEthernet0/1, Cost of using 10 Transmit Delay is 1 sec, State POINT_TO_POINT, Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:07 Adjacency State FULL Based on this output, what can be concluded?
17A network engineer issues the following command on Router R8: R8# show ip ospf neighbor detail Neighbor 1.1.1.1, interface address 192.168.1.1 In the area 0 via interface GigabitEthernet0/0 Neighbor priority is 1, State is FULL, 6 state changes DR is 192.168.1.2, BDR is 192.168.1.1 Options is 0x42 (L LSR LSRR L LSR) Dead timer due in 00:00:34 Neighbor is up for 00:12:45 Index 1/1/1, retransmission queue length 0, number of retransmission 0 First 0x0(0)/0x0(0)/0x0(0) Next 0x0(0)/0x0(0)/0x0(0) Last retransmission scan length is 0, last retransmission scan time is 0 msec Based on this output, what can be concluded?
18A network engineer runs the following command on Router R9: R9# show ip ospf interface brief Interface PID Area IP Address/Mask Cost State Nbrs F/C Gi0/0 1 0 192.168.1.9/24 10 DR 2/2 Gi0/1 1 1 10.0.0.9/24 20 BDR 1/1 Lo0 1 0 9.9.9.9/32 1 LOOP 0/0 Based on this output, what can be concluded?
19Router R1 has the following OSPF configuration: interface GigabitEthernet0/0 ip address 10.1.1.1 255.255.255.0 ip ospf 1 area 0 ip ospf network point-to-point ! router ospf 1 router-id 1.1.1.1 network 10.0.0.0 0.255.255.255 area 0 What is the effect of the 'ip ospf network point-to-point' command on this interface?
20Consider the following OSPF configuration on router R2: interface GigabitEthernet0/0 ip address 192.168.1.2 255.255.255.0 ip ospf 1 area 0 ip ospf hello-interval 5 ! router ospf 1 router-id 2.2.2.2 network 192.168.1.0 0.0.0.255 area 0 Which statement is true about this configuration?
21Router R3 has the following OSPF configuration: router ospf 1 router-id 3.3.3.3 network 10.0.0.0 0.255.255.255 area 0 default-information originate always metric 20 metric-type 2 What is the effect of the 'default-information originate always' command?
22Examine this OSPF configuration on router R4: interface GigabitEthernet0/0 ip address 172.16.1.4 255.255.255.0 ip ospf 1 area 0 ip ospf cost 50 ! router ospf 1 router-id 4.4.4.4 network 172.16.0.0 0.0.255.255 area 0 What is the OSPF cost of the GigabitEthernet0/0 interface?
23Router R5 has the following OSPF configuration: router ospf 1 router-id 5.5.5.5 network 10.0.0.0 0.255.255.255 area 0 area 0 authentication message-digest ! interface GigabitEthernet0/0 ip address 10.1.1.5 255.255.255.0 ip ospf message-digest-key 1 md5 cisco123 What is missing from this OSPF authentication configuration?
24Router R6 has the following OSPF configuration: router ospf 1 router-id 6.6.6.6 network 192.168.0.0 0.0.255.255 area 0 passive-interface default no passive-interface GigabitEthernet0/0 ! interface GigabitEthernet0/0 ip address 192.168.1.6 255.255.255.0 ip ospf 1 area 0 What is the effect of the 'passive-interface default' command?
25What is the default OSPF hello interval on a broadcast multi-access network (e.g., Ethernet)?
26In OSPF, which LSA type is used to describe routes to networks within the same area and is generated by the router that owns the network?
27What is the default OSPF reference bandwidth used for cost calculation in Cisco IOS?
28Drag and drop the steps of OSPF neighbor adjacency formation into the correct order, from first to last.
29Drag and drop the steps of OSPF route redistribution into a different autonomous system into the correct order, from first to last.
30Drag and drop the steps of OSPF virtual link configuration into the correct order, from first to last.
31Drag and drop the steps of OSPF SPF calculation steps (Dijkstra) into the correct order, from first to last.
32Drag and drop the steps of OSPFv3 IPv6 neighbor adjacency formation into the correct order, from first to last.
33Drag and drop the steps of OSPF redistribution from EIGRP with metric conversion into the correct order, from first to last.
34Drag and drop the steps of OSPF virtual link configuration across area 0 into the correct order, from first to last.
35Drag and drop the steps of OSPF summarization at ABR configuration steps into the correct order, from first to last.
36Drag and drop the steps of OSPF SPF calculation steps (Dijkstra) into the correct order, from first to last.
37Drag and drop the steps of OSPFv3 IPv6 neighbor adjacency formation into the correct order, from first to last.
38Drag and drop the steps of OSPF redistribution from EIGRP with metric conversion into the correct order, from first to last.
39Drag and drop the steps of OSPF virtual link configuration across area 0 into the correct order, from first to last.
40Drag and drop the steps of OSPF summarization at ABR configuration steps into the correct order, from first to last.
41Drag and drop each OSPF LSA type on the left to its matching description on the right.
42Drag and drop each OSPF packet type on the left to its matching function on the right.
43Drag and drop each OSPF area type on the left to its matching characteristic on the right.
44Drag and drop each OSPF router role on the left to its matching function on the right.
45Drag and drop each OSPF network type on the left to its matching DR election behavior on the right.
46Drag and drop each OSPF LSA type on the left to its matching description on the right.
47Drag and drop each OSPF packet type on the left to its matching function on the right.
48Drag and drop each OSPF area type on the left to its matching characteristic on the right.
49Drag and drop each OSPF router role on the left to its matching function on the right.
50Drag and drop each OSPF network type on the left to its matching DR election behavior on the right.
51Which two statements about OSPF network types are true? (Choose two.)
52Which three statements about OSPF LSA types are correct? (Choose three.)
53Which two statements about OSPF neighbor states are true? (Choose two.)
54Which three statements about OSPF area types are correct? (Choose three.)
55Which two statements about OSPF network types are true? (Choose two.)
56Which three statements about OSPF LSA types are true? (Choose three.)
57Which two statements about OSPF neighbor states are true? (Choose two.)
58Which three statements about OSPF route summarization are true? (Choose three.)
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