OSPF Flashcards
Link state topology that uses Dijkstra algorithm to compute routing information
OSPF
Collection of networks and routers that have the same area identification. The identifier is locally significant.
OSPF area
How is the OSPF router ID determined?
Configuration with router-id command Highest numbered IP address of loopback Highest numbered IP address of physical interface If no interface exists, set router ID to 0.0.0.0
Command that is used to manually set which router becomes the DR (Designated Router)
OSPF priority
When two or more routers are contending to be a DR on a network segment, how is the DR chosen?
Highest OSPF priority
Router type with an interface in area0
backbone
Router that connects two or more areas
Area Border Router (ABR)
Connects to additional routing domains; typically located in the backbone
AS Boundary Router (ASBR)
What is the default administrative distance of OSPF?
110
Routers receive these updates containing information about an OSPF area.
Link State Advertisements (LSA)
When routers receives LSAs from other OSPF routers, what database is populated?
Link State Database
What kind of route is populated into the routing table?
best path
Routers that reside on the same network link and exchange hello messages.
Neighbors
Neighbor routers that have exchanged Link State Updates (LSU) and Database Description (DD) packets.
Adjacencies
When forming an adjacency, what state do both routers begin in?
Init
R1 sends a Hello packet to R2. R2 does not see its own router ID and sends a Hello packet back. When R1 receives this packet and sees its own router ID, what state does R1 transition to?
2 way
What state is the DR and BDR selected in?
2 way
What state is the primary and designated router selected in?
ExStart
The actual exchange of database information happens in what state?
Exchange
The _____ router sends out database description packets to the _____ router and the secondary router sends an acknowledgment
primary secondary
What packet contains a list of the LSAs known to the router?
DD packet
If R1 sees that it is missing an LSA from the DD packet, what does it do?
Responds with a Link State Request (LS)
In what state does a router send LS for missing LSAs?
Loading state
Once all of the missing pieces of the puzzle are completed, both routers should have identical link state databases on these two routers. What is the state when an adjacency is formed?
Full state
A logical link that interconnects the backbone area with an area that is not adjacent to the backbone area.
virtual link
What kind of packet helps ensure a reliable transmission of LSAs
LSA Acknowledgement
What command enables the OSPF routing process for process-id 1?
router ospf 1
What command identifies the networks that you want to advertise for area 1?
network [ip address] [wildcard mask] area 1
Instead of identifying networks, you can alternatively enable OSPF on an interface with what command?
ip ospf [process-id] area [area-id]
In order to route towards external networks or toward the internet, what must the router know?
destination network or default route
What command is used for a router that announce the default route? What keyword can be added to the end to always announce the default route?
default-information originate always
What two commands allow you to verify OSPF configuration?
show run | section ospf show ip protocols
What command displays which interfaces are enabled for the OSPF routing process? Useful to determine if your network statements were correctly composed.
show ip ospf interface brief
What command displays OSPF related information on interface FastEthernet 0/1?
show ip ospf interface f0/1
What command displays the OSPF neighbors?
show ip ospf neighbor
What command displays the content of the routing table?
show ip route
By default on Cisco devices, what is the cost calculation based on?
interface bandwidth
What is the formula to determine cost?
cost = reference bandwidth / interface bandwidth
What is the default reference bandwidth?
100
What is the cost for all links that are faster than FastEthernet?
1
What command allows you to configure the reference bandwidth?
ospf auto-cost reference bandwidth [reference-bandwidth]
What command allows you to change the interface cost?
ip ospf cost [cost]
What command allows you to change the bandwidth?
bandwidth [kbps]
The cumulative cost of all links on the path to destinations
path cost
A _____ interface surpasses inbound and outbound OSPF packets on the interface. The interface no longer sends and receives Hello packets and will not become neighbors.
passive
What command configures a specific interface as passive for the OSPF routing protocol on FastEthernet0/1?
passive-interface f0/1
What command configures all interfaces, except FastEthernet0/2, as passive for the OSPF routing protocol
passive-interface default no passive-interface f0/2
What command displays the number of times that the SPF algorithm has been executed?
show ip ospf
What area must all other areas directly connect to?
Backbone area
What are the characteristics of the ABR?
Separates LSA flooding zones Becomes primary point for area address summarization Functions regularly as source for default routes Maintains the LSDB for each area it is connected to
How does OSPFv3 communicate?
By using IPv6 multicast addresses
Is OSPFv3 enabled per network?
No. Enabled per link
What type of addresses does OSPFv3 adjacencies use to communicate?
link-local
What IPv6 protocol number is used to transport LSAs?
89
What multicast address is used by OSPFv3 for all OSPF routers?
FF02::5
What multicast address is used by OSPFv3 for the DR and BDR?
FF02::6
What must be configured on a router so that OSPFv3 can obtain the router ID? If not the router ID must be configured manually.
IPv4
What command enables IPv6 routing?
ipv6 unicast-routing
What command enables the OSPFv3 routing process with a process ID of 1?
ipv6 router ospf 1
What command enables OSPFv3 on an interface?
ipv6 ospf [process-id] [area-id]
What command shows a summary of the configured IPv6 routing protocol information? You can see which protocols are enabled and which networks these protocols are routing for
show ipv6 protocols
What are the major components of OSPF troubleshooting?
OSPF neighbor adjacencies OSPF routing table OSPF path selection
When you are notified that there are connectivity issues in your network, you should first test connectivity with what commands?
ping traceroute
What should you look into next if the neighbor table does not hold all of the devices that you expect?
Are interfaces operational Are interfaces enabled for OSPF Does OSPF area match Is an interface configured as passive
After you verify that the neighbor table holds all of the devices that you expect, what should you look into next?
Does the routing table have all necessary routes
If the routing table does not have all necessary routes, what should you troubleshoot?
Are the networks being advertised Is there a routing source with a lower AD Are all areas connected to Area 0
After you verify that the routing table has all of the necessary routes, what should you look into next?
Does the traffic take the desired path
If the traffic does not take the desired path, what should you troubleshoot?
Verify the OSPF cost on an interface Verify the OSPF reference bandwidth
What commands could be used to determine if the traffic is taking the desired path?
show ip route show ip ospf
What commands show passive interfaces?
show ip protocols show ip ospf interface show run
What could be a reason that two OSPF routes are installed in the routing table to the same network?
Equal cost
What command displays information about the OSPF LSAs in the link state table (database)?
show ip ospf database
What command displays information about the DR and BDR?
show ip ospf neighbor
What command displays the router ID, OSPF priority, OSPF state, IP address, and local router interface connected to neighbor
show ip ospf neighbor
What type of mismatch could prevent OSPF interfaces from forming an adjacency if the mismatch is detected during the DBD packet exchange?
MTU
What command configures OSPF to ignore MTU mismatches?
ip ospf mtg-ignore
Will a mismatched process ID prevent OSPF routers from communicating?
No process ID is locally significant
What command configures an interface to reside in OSPFv3 Area 0?
ipv6 ospf 10 area 0.0.0.0
By default, an OSPF router can insert a maximum of ____ equal-cost paths into the routing table.
4
Do hello timer values, dead timer values, and authentication passwords need to match between routers in order to form an adjacency?
Yes
What are the five types of LSAs that are stored in an OSPF link-state database?
Router Link - Type 1 Network Link - Type 2 Summary Link to networks - Type 3 Summary Link to ASBRs - Type 4 AS external link - Type 5
What prompt indicates that the router is in OSPFv3 configuration mode and not OSPF router configuration mode for Router A?
RouterA (config-rtr)#
What is the multicast address for all OSPF routers?
224.0.0.5
What is the multicast address for designated OSPF routers?
224.0.0.6
By default, an OSPFv3 instance automatically includes what?
All IPv6 prefixes configured on that interface
Can a single IPv6 link be configured with multiple OSPFv3 instances?
Yes
What command would enable OSPF area 10 to interface FastEthernet0/1? Note: Interface IP address 192.168.2.0
interface f0/1 ip ospf 10 area 0
What command allows you to view whether the OSPF router is an ABR or ASBR? It also shows the number of OSPF areas that are configured on a router and how many of those areas are normal areas, stub areas, or not-so-stubby areas.
show ip ospf
Summaries of all Type 1 and Type 2 LSAs in a given area and are only sent by ABRs.
Type 3 LSA
What command will show if interface FastEthernet0/0 has any OSPF neighbors or adjacencies?
show ip ospf int f0/0
In what state do OSPF routers exchange DBD packets?
ExStart
What do DBD packets contain?
Information about each router’s LSDB, including information about LSAs that are stored in the LSDBs
What is the default priority of an ospf router?
1
What is the priority range of an ospf router?
0 - 255
During the DR election, if the router’s priority values tie, how is the DR elected?
highest router id
What is the default Hello timer in a Non-Broadcast (NMBA) network?
30 seconds
What are two drawbacks of implementing a link-state routing protocol? (Choose two)
- The sequencing and acknowledgement of link-state packets
- The requirement for a hierarchical IP addressing scheme for optimal functionality
- The high volume of link-state advertisements in a converged network
- The high demand on router resources to run the link-state routing algorithm
- The large size of the topology table listing all advertised routes in the converged network
- The requirement for a hierarchical IP addressing scheme for optimal functionality
- The high demand on router resources to run the link-state routing algorithm
What are three characteristics of the OSPF routing protocol? (Choose three)
- It converges quickly
- OSPF is a classful routing protocol
- It uses cost to determine the best route
- It uses DUAL algorithm to determine the best route
- OSPF routers send the complete routing table to all directly attached routers
- OSPF routers discover neighbors before exchanging routing information
- It converges quickly
- It uses cost to determine the best route
- OSPF routers discover neighbors before exchanging routing information
What are two enhancements that OSPFv3 supports over OSPFv2? (Choose two)
- It requires the use of ARP
- It can support multiple IPv6 subnets on a single link
- It supports up to 2 instances of OSPFv3 over a common link
- It routes over links rather than over networks
It can support multiple IPv6 subnets on a single link
It routes over links rather than over networks
What are the two drawbacks of implementing a link-state routing protocol?
The requirement for a hierarchical IP addressing scheme for optimal functionality The high demand on a router resources to run the link-state routing algorithm
Which commands are required to properly configure a router to run OSPF and to add network 192.168.16.0/24 to OSPF area 0? (Choose two)
- Router(config)# router ospf 0
- Router(config)# router ospf 1
- Router(config)# router ospf area 0
- Router(config-router)# network 192.168.16.0 0.0.0.255 0
- Router(config-router)#network 192.168.16.0 0.0.0.255 area 0
- Router(config-router)# network 192.168.16.0 255.255.255.0 area 0
- router ospf 1
- network 192.168.16.0 0.0.0.255 area 0
Cisco routers can support up to ____ equal-cost paths
16
Refer to the exhibit. Assume that all of the router interfaces are operational and configured correctly. How will router R2 be affected by the configuration of R1 that is shown in the exhibit?
- Router R2 will not form a neighbor relationship with R1.
- Router R2 will obtain a full routing table, including a default route, from R1.
- R2 will obtain OSPF updates from R1, but will not obtain a default route from R1.
- R2 will not have a route for the directly connected serial network, but all other directly connected networks will be present, as well as the two Ethernet networks connected to R1.
Router R2 will not form a neighbor relationship with R1
Refer to the exhibit. RTA is configured with a basic configuration. The link between the two routers is operational and no routing protocols are configured on either router. The line shown in the exhibit is then added to router RTA . Should interface Fa0/0 on router RTB shut down, what effect will the shutdown have on router RTA?
A. A route to 172.16.14.0/24 will remain in the RTA routing table.
B. A packet to host 172.16.14.225 will be dropped by router RTA
C. Router RTA will send an ICMP packet to attempt to verify the route.
D. Because router RTB will send a poison reverse packet to router RTA, RTA will remove the route.
A. A route to 172.16.14.0/24 will remain in the RTA routing table.
Refer to the exhibit. Assume that all of the router interfaces are operational and configured correctly. How will router R2 be affected by the configuration of R1 that is shown in the exhibit?
A. Router R2 will not form a neighbor relationship with R1.
B. Router R2 will obtain a full routing table, including a default route, from R1.
C. R2 will obtain OSPF updates from R1, but will not obtain a default route from R1.
D. R2 will not have a route for the directly connected serial network, but all other directly connected networks will be present, as well as the two Ethernet networks connected to R1.
A. Router R2 will not form a neighbor relationship with R1.
Refer to the exhibit. Assume that all router interfaces are operational and correctly configured. In addition, assume that OSPF has been correctly configured on router R2. How will the default route configured on R1 affect the operation of R2?
A. Any packet destined for a network that is not directly connected to router R1 will be dropped.
B. Any packet destined for a network that is not directly connected to router R2 will be dropped immediately.
C. Any packet destined for a network that is not directly connected to router R2 will be dropped immediately because of the lack of a gateway on R1.
D. The networks directly connected to router R2 will not be able to communicate with the 172.16.100.0, 172.16.100.128, and 172.16.100.64 subnetworks.
E. Any packet destined for a network that is not referenced in the routing table of router R2 will be directed to R1. R1 will then send that packet back to R2 and a routing loop will occur.
E. Any packet destined for a network that is not referenced in the routing table of router R2 will be directed to R1. R1 will then send that packet back to R2 and a routing loop will occur.
Which command is used to display the collection of OSPF link states?
A. show ip ospf link-state
B. show ip ospf lsa database
C. show ip ospf neighbors
D. show ip ospf database
D. show ip ospf database
Refer to the exhibit. The network is converged.
After link-state advertisements are received from Router_A, what information will Router_E contain in its routing table for the subnets 208.149.23.64 and 208.149.23.96?
A. O 208.149.23.64 [110/13] via 190.173.23.10, 00:00:07, FastEthernet 0/0 O 208.149.23.96 [110/13] via 190.173.23.10, 00:00:16, FastEthernet 0/0
B. O 208.149.23.64 [110/1] via 190.172.23.10, 00:00:07, Serial 1/0 O 208.149.23.96 [110/3] via 190.173.23.10, 00:00:16, FastEthernet 0/0
C. O 208.149.23.64 [110/13] via 190.172.23.10, 00:00:07, Serial 1/0 O 208.149.23.96 [110/13] via 190.172.23.10, 00:00:16, Serial 1/0 O 208.149.23.96 [110/13] via 190.173.23.10, 00:00:16, FastEthernet 0/0
D. O 208.149.23.64 [110/3] via 190.172.23.10, 00:00:07, Serial 1/0 O 208.149.23.96 [110/3] via 190.172.23.10, 00:00:16, Serial 1/0
A. O 208.149.23.64 [110/13] via 190.173.23.10, 00:00:07, FastEthernet 0/0 O 208.149.23.96 [110/13] via 190.173.23.10, 00:00:16, FastEthernet 0/0
The internetwork infrastructure of company XYZ consists of a single OSPF area as shown in the graphic. There is concern that a lack of router resources is impeding internetwork performance.
As part of examining the router resources, the OSPF DRs need to be known. All the router OSPF priorities are at the default and the router IDs are shown with each router.
Which routers are likely to have been elected as DR? (Choose two.)
A. Corp-1
B. Corp-2
C. Corp-3
D. Corp-4
E. Branch-1
F. Branch-2
D. Corp-4
F. Branch-2
Refer to the exhibit. Given the output for this command, if the router ID has not been manually set, what router ID will OSPF use for this router?
A. 10.1.1.2
B. 10.154.154.1
C. 172.16.5.1
D. 192.168.5.3
C. 172.16.5.1
What is the default maximum number of equal-cost paths that can be placed into the routing table of a Cisco OSPF router?
A. 2
B. 4
C. 16
D. unlimited
B. 4
Refer to the exhibit. Which two statements are true about the loopback address that is configured on RouterB? (Choose two.)
A. It ensures that data will be forwarded by RouterB.
B. It provides stability for the OSPF process on RouterB.
C. It specifies that the router ID for RouterB should be 10.0.0.1.
D. It decreases the metric for routes that are advertised from RouterB.
E. It indicates that RouterB should be elected the DR for the LAN.
B. It provides stability for the OSPF process on RouterB.
C. It specifies that the router ID for RouterB should be 10.0.0.1.
Refer to the exhibit. The network associate is configuring OSPF on the Core router. All the connections to the branches should be participating in OSPF. The link to the ISP should NOT participate in OSPF and should only be advertised as the default route. What set of commands will properly configure the Core router?
A. Core(config-router)# default-information originate
Core(config-router)# network 10.0.0.0 0.255.255.255 area 0
Core(config-router)# exit
Core(config)# ip route 0.0.0.0 0.0.0.0 10.10.2.14
B. Core(config-router)# default-information originate
Core(config-router)# network 10.10.2.13 0.0.0.242 area 0
Core(config-router)# exit
Core(config)# ip route 0.0.0.0 0.0.0.0 10.10.2.14
C. Core(config-router)# default-information originate
Core(config-router)# network 10.10.2.16 0.0.0.15 area 0
Core(config-router)# exit
Core(config)# ip route 0.0.0.0 0.0.0.0 10.10.2.14
D. Core(config-router)# default-information originate
Core(config-router)# network 10.10.2.32 0.0.0.31 area 0
Core(config-router)# exit
Core(config)# ip route 0.0.0.0 0.0.0.0 10.10.2.14
C. Core(config-router)# default-information originate
Core(config-router)# network 10.10.2.16 0.0.0.15 area 0
Core(config-router)# exit
Core(config)# ip route 0.0.0.0 0.0.0.0 10.10.2.14
Which parameter or parameters are used to calculate OSPF cost in Cisco routers?
A. Bandwidth
B. Bandwidth and Delay
C. Bandwidth, Delay, and MTU
D. Bandwidth, MTU, Reliability, Delay, and Load
A. Bandwidth
Which statement is true, as relates to classful or classless routing?
A. Classful routing protocols send the subnet mask in routing updates.
B. RIPv1 and OSPF are classless routing protocols.
C. Automatic summarization at classful boundaries can cause problems on discontiguous subnets.
D. EIGRP and OSPF are classful routing protocols and summarize routes by default.
C. Automatic summarization at classful boundaries can cause problems on discontiguous subnets.
What are three characteristics of the OSPF routing protocol? (Choose three.)
A. It converges quickly.
B. OSPF is a classful routing protocol.
C. It uses cost to determine the best route.
D. It uses the DUAL algorithm to determine the best route.
E. OSPF routers send the complete routing table to all directly attached routers.
F. OSPF routers discover neighbors before exchanging routing information.
A. It converges quickly.
C. It uses cost to determine the best route.
F. OSPF routers discover neighbors before exchanging routing information.
When a router undergoes the exchange protocol within OSPF, in what order does it pass through each state?
A. exstart state > loading state > exchange state > full state
B. exstart state > exchange state > loading state > full state
C. exstart state > full state > loading state > exchange state
D. loading state > exchange state > full state > exstart state
B. exstart state > exchange state > loading state > full state
Which statement describes the process ID that is used to run OSPF on a router?
A. It is globally significant and is used to represent the AS number.
B. It is locally significant and is used to identify an instance of the OSPF database.
C. It is globally significant and is used to identify OSPF stub areas.
D. It is locally significant and must be the same throughout an area.
B. It is locally significant and is used to identify an instance of the OSPF database.
What can cause two OSPF neighbors to be stuck in the EXSTART state?
A. There is a low bandwidth connection between neighbors.
B. The neighbors have different MTU settings.
D. There is only layer one connectivity between neighbors.
C. The OSPF interfaces are in a passive state.
B. The neighbors have different MTU settings.
What are two benefits of using a single OSPF area network design? (Choose two.)
A. It is less CPU intensive for routers in the single area.
B. It reduces the types of LSAs that are generated.
C. It removes the need for virtual links.
D. It increases LSA response times.
E. It reduces the number of required OSPF neighbor adjacencies.
B. It reduces the types of LSAs that are generated.
C. It removes the need for virtual links.
Refer to the exhibit. If the router Cisco returns the given output and has not had its router ID set manually, what value will OSPF use as its router ID?
A. 192.168.1.1
B. 172.16.1.1
C. 1.1.1.1
D. 2.2.2.2
D. 2.2.2.2
What OSPF command, when configured, will include all interfaces into area 0?
A. network 0.0.0.0 255.255.255.255 area 0
B. network 0.0.0.0 0.0.0.0 area 0
C. network 255.255.255.255 0.0.0.0 area 0
D. network all-interfaces area 0
A. network 0.0.0.0 255.255.255.255 area 0
Which two statements about the OSPF Router ID are true? (Choose two.)
A. It identifies the source of a Type 1 LSA.
B. It should be the same on all routers in an OSPF routing instance.
C. By default, the lowest IP address on the router becomes the OSPF Router ID.
D. The router automatically chooses the IP address of a loopback as the OSPF Router ID.
E. It is created using the MAC Address of the loopback interface.
A. It identifies the source of a Type 1 LSA.
D. The router automatically chooses the IP address of a loopback as the OSPF Router ID.
Refer to the exhibit. To what does the 128 refer in the router output O 168.12.240/30 [110/128] via 192.168.12.233,00:35:36, Serial 0?
A. OSPF cost
B. OSPF priority
C. OSPF hop count
D. OSPF ID number
E. OSPF administrative distance
A. OSPF cost
A network administrator is configuring the routers in the graphic for OSPF. The OSPF process has been started and the networks have been configured for Area 0 as shown in the diagram. The network administrator has several options for configuring RouterB to ensure that it will be preferred as the designated router (DR) for the 172.16.1.0 /24 LAN segment. What configuration tasks could be used to establish this preference? (Choose three.)
A. Configure the priority value of the Fa0/0 interface of RouterB to a higher value than any other interface on the Ethernet network.
B. Change the router id of Router B by assigning the IP address 172.16.1.130/24 to the Fa0/0 interface of RouterB.
C. Configure a loopback interface on RouterB with an IP address higher than any IP address on the other routers.
D. Change the priority value of the Fa0/0 interface of RouterB to zero.
E. Change the priority values of the Fa0/0 interfaces of RouterA and RouterC to zero.
F. No further configuration is necessary.
A. Configure the priority value of the Fa0/0 interface of RouterB to a higher value than any other interface on the Ethernet network.
C. Configure a loopback interface on RouterB with an IP address higher than any IP address on the other routers.
E. Change the priority values of the Fa0/0 interfaces of RouterA and RouterC to zero.
Refer to the exhibit. What can be concluded from the output of the debug command?
A. The output represents normal OSPF operation.
B. The interfaces of two OSPF routers connected to the Border router are in the same subnet.
C. The OSPF router connected to interface Serial0/1 has NOT formed a neighbor relationship with the Border router.
D. A router is connected to interface Serial0/3 of the Border router. The OSPF router ID of the connected router is the IP address of the connected interface.
Refer to the exhibit. What can be concluded from the output of the debug command?
Refer to the exhibit. You are connected to the router as user Mike. Which command allows you to see output from the OSPF debug command?
A. terminal monitor
B. show debugging
C. show sessions
D. show ip ospf interface
A. terminal monitor
What are three characteristics of the OSPF routing protocol? (Choose three.)
A. It converges quickly.
B. OSPF is a classful routing protocol.
C. It uses cost to determine the best route.
D. It uses the DUAL algorithm to determine the best route.
E. OSPF routers send the complete routing table to all directly attached routers.
F. OSPF routers discover neighbors before exchanging routing information.
A. It converges quickly.
C. It uses cost to determine the best route.
F. OSPF routers discover neighbors before exchanging routing information.
What are two enhancements that OSPFv3 supports over OSPFv2? (Choose two.)
A. It requires the use of ARP.
B. It can support multiple IPv6 subnets on a single link.
C. It supports up to 2 instances of OSPFv3 over a common link.
D. It routes over links rather than over networks.
B. It can support multiple IPv6 subnets on a single link.
D. It routes over links rather than over networks.
R1 is configured with the default configuration of OSPF.
From the following list of IP addresses configured on R1, which address will the OSPF process select as the router ID?
A. 192.168.0.1
B. 172.16.1.1
C. 172.16.2.1
D. 172.16.2.225
A. 192.168.0.1
To allow or prevent load balancing to network 172.16.3.0/24, which of the following commands could be used in R2? (Choose two.)
A. R2(config-if)#clock rate
B. R2(config-if)#bandwidth
C. R2(config-if)#ip ospf cost
D. R2(config-if)#ip ospf priority
E. R2(config-router)#distance ospf
B. R2(config-if)#bandwidth
C. R2(config-if)#ip ospf cost
After the network has converged, what type of messaging, if any, occurs between R3 and R4?
A. No messages are exchanged.
B. Hellos are sent every 10 seconds.
C. The full database from each router is sent every 30 seconds.
D. The routing table from each router is sent every 60 seconds.
B. Hellos are sent every 10 seconds.
OSPF is configured using default classful addressing. With all routers and interfaces operational, how many networks will be in the routing table of R1 that are indicated to be learned by OSPF?
A. 2
B. 3
C. 4
D. 5
E. 6
F. 7
C. 4
Drag and Drop Question
Drag the term on the left to its definition on the right (Not all options are used.)
Drag and Drop Question
Drag the term on the left to its definition on the right (Not all options are used.)
Which commands are required to properly configure a router to run OSPF and to add network 192.168.16.0/24 to OSPF area 0? (Choose two.)
A. Router(config)# router ospf 0
B. Router(config)# router ospf 1
C. Router(config)# router ospf area 0
D. Router(config-router)# network 192.168.16.0 0.0.0.255 0
E. Router(config-router)# network 192.168.16.0 0.0.0.255 area 0
F. Router(config-router)# network 192.168.16.0 255.255.255.0 area 0
B. Router(config)# router ospf 1
E. Router(config-router)# network 192.168.16.0 0.0.0.255 area 0
What information does a router running a link-state protocol use to build and maintain its topological database? (Choose two.)
A. hello packets
B. SAP messages sent by other routers
C. LSAs from other routers
D. beacons received on point-to-point links
E. routing tables received from other link-state routers
F. TTL packets from designated routers
A. hello packets
C. LSAs from other routers
Refer to the exhibit. A network associate has configured OSPF with the command:
City(config-router)# network 192.168.12.64 0.0.0.63 area 0
After completing the configuration, the associate discovers that not all the interfaces are participating in OSPF. Which three of the interfaces shown in the exhibit will participate in OSPF according to this configuration statement? (Choose three.)
A. FastEthernet0 /0
B. FastEthernet0 /1
C. Serial0/0
D. Serial0/1.102
E. Serial0/1.103
F. Serial0/1.104
B. FastEthernet0 /1
C. Serial0/0
D. Serial0/1.102
Which two statements describe the process identifier that is used in the command to configure OSPF on a router? (Choose two.)
Router(config)# router ospf 1
A. All OSPF routers in an area must have the same process ID.
B. Only one process number can be used on the same router.
C. Different process identifiers can be used to run multiple OSPF processes
D. The process number can be any number from 1 to 65,535.
E. Hello packets are sent to each neighbor to determine the processor identifier.
C. Different process identifiers can be used to run multiple OSPF processes
D. The process number can be any number from 1 to 65,535.
The internetwork infrastructure of company XYZ consists of a single OSPF area as shown in the graphic. There is concern that a lack of router resources is impeding internetwork performance. As part of examining the router resources, the OSPF DRs need to be known. All the router OSPF priorities are at the default and the router IDs are shown with each router. Which routers are likely to have been elected as DR? (Choose two.)
A. Corp-1
B. Corp-2
C. Corp-3
D. Corp-4
E. Branch-1
F. Branch-2
D. Corp-4
E. Branch-1
You enter the show ipv6 route command on an OSPF device and the device displays a route.
Which conclusion can you draw about the environment?
A. OSPF is distributing IPv6 routes to BGP.
B. The router is designated as an ABR.
C. The router is designated as totally stubby.
D. OSPFv3 is in use.
D. OSPFv3 is in use.
Refer to the exhibit. Router edge-1 is unable to establish OSPF neighbor adjacency with router ISP-1. Which two configuration changes can you make on edge-1 to allow the two routers to establish adjacency? (Choose two.)
A. Set the subnet mask on edge-1 to 255 255.255.252.
B. Reduce the MTU on edge-1 to 1514.
C. Set the OSPF cost on edge-1 to 1522.
D. Reduce the MTU on edge-1 to 1500.
E. Configure the ip ospf mtu-ignore command on the edge-1 Gi0/0 interface.
D. Reduce the MTU on edge-1 to 1500.
E. Configure the ip ospf mtu-ignore command on the edge-1 Gi0/0 interface.
