Enterprise Networking 1-2

In an OSPFv2 configuration, what is the effect of entering the command network 192.168.1.1 0.0.0.0 area 0 ? It changes the router ID of the router to 192.168.1.1. It enables OSPF on all interfaces on the router. It tells the router which interface to turn on for the OSPF routing process. It allows all 192.168.1.0 networks to be advertised.

It tells the router which interface to turn on for the OSPF routing process.

In an OSPF network when are DR and BDR elections required? when all the routers in an OSPF area cannot form adjacencies when the two adjacent neighbors are in two different networks when the routers are interconnected over a common Ethernet network when the two adjacent neighbors are interconnected over a point-to-point link

when the routers are interconnected over a common Ethernet network

An administrator is configuring single-area OSPF on a router. One of the networks that must be advertised is 64.102.0.0 255.255.255.128. What wildcard mask would the administrator use in the OSPF network statement? 0.0.0.127 0.0.0.63 0.0.0.31 0.0.0.15

0.0.0.127

An administrator is configuring single-area OSPF on a router. One of the networks that must be advertised is 64.100.0.0 255.255.255.0. What wildcard mask would the administrator use in the OSPF network statement? 0.0.0.255 0.0.0.127 0.0.0.63 0.0.0.31

0.0.0.255

An administrator is configuring single-area OSPF on a router. One of the networks that must be advertised is 128.107.0.0 255.255.255.192. What wildcard mask would the administrator use in the OSPF network statement? 0.0.0.63 0.0.0.3 0.0.0.7 0.0.63.255

0.0.0.63

An administrator is configuring single-area OSPF on a router. One of the networks that must be advertised is 192.168.223.0 255.255.254.0. What wildcard mask would the administrator use in the OSPF network statement? 0.0.1.255 0.0.7.255 0.0.15.255 0.0.31.255

0.0.1.255

An administrator is configuring single-area OSPF on a router. One of the networks that must be advertised is 128.107.0.0 255.255.252.0. What wildcard mask would the administrator use in the OSPF network statement? 0.0.3.255 0.0.0.3 0.0.0.7 0.0.63.255

0.0.3.255

An administrator is configuring single-area OSPF on a router. One of the networks that must be advertised is 198.19.0.0 255.255.252.0. What wildcard mask would the administrator use in the OSPF network statement? 0.0.3.255 0.0.31.255 0.0.63.255 0.0.0.255

0.0.3.255

By default, what is the OSPF cost for any link with a bandwidth of 100 Mb/s or greater? 1 100 10000 100000000

1

What is the default router priority value for all Cisco OSPF routers? 0 1 10 255

1

What is the recommended Cisco best practice for configuring an OSPF-enabled router so that each router can be easily identified when troubleshooting routing issues? Use the highest IP address assigned to an active interface participating in the routing process. Configure a value using the router-id command. Use the highest active interface IP address that is configured on the router. Use a loopback interface configured with the highest IP address on the router.

Configure a value using the router-id command.

After modifying the router ID on an OSPF router, what is the preferred method to make the new router ID effective? HQ# copy running-config startup-config HQ# clear ip ospf process HQ# clear ip route * HQ# resume

HQ# clear ip ospf process

Which three OSPF states are involved when two routers are forming an adjacency? (Choose three.) Init Down ExStart Loading Two-way Exchange

Init Down Two-way

A network engineer has manually configured the hello interval to 15 seconds on an interface of a router that is running OSPFv2. By default, how will the dead interval on the interface be affected? The dead interval will now be 15 seconds. The dead interval will now be 30 seconds. The dead interval will now be 60 seconds. The dead interval will not change from the default value.

The dead interval will now be 60 seconds.

What is a benefit of multiarea OSPF routing? Topology changes in one area do not cause SPF recalculations in other areas. Automatic route summarization occurs by default between areas. Routers in all areas share the same link-state database and have a complete picture of the entire network. A backbone area is not required.

Topology changes in one area do not cause SPF recalculations in other areas.

What is the format of the router ID on an OSPF-enabled router? a character string with no space a 32-bit number formatted like an IPv4 address a unique phrase with no more than 16 characters a unique router host name that is configured on the router an 8-bit number with a decimal value between 0 and 255

a 32-bit number formatted like an IPv4 address

What will an OSPF router prefer to use first as a router ID? any IP address that is configured using the router-id command a loopback interface that is configured with the highest IP address on the router the highest active interface IP that is configured on the router the highest active interface that participates in the routing process because of a specifically configured network statement

any IP address that is configured using the router-id command

Which step in the link-state routing process is described by a router building a link-state database based on received LSAs? building the topology table executing the SPF algorithm selecting the router ID declaring a neighbor to be inaccessible

building the topology table

Which step in the link-state routing process is described by a router inserting best paths into the routing table? choosing the best route executing the SPF algorithm load balancing equal-cost paths declaring a neighbor to be inaccessible

choosing the best route

Which type of OSPFv2 packet contains an abbreviated list of the LSDB of a sending router and is used by receiving routers to check against the local LSDB? link-state update link-state request database description link-state acknowledgment

database description

Which step in the link-state routing process is described by a router sending Hello packets out all of the OSPF-enabled interfaces? establishing neighbor adjacencies exchanging link-state advertisements electing the designated router injecting the default route

establishing neighbor adjacencies

When an OSPF network is converged and no network topology change has been detected by a router, how often will LSU packets be sent to neighboring routers? every 5 minutes every 10 minutes every 30 minutes every 60 minutes

every 30 minutes

Which step does an OSPF-enabled router take immediately after establishing an adjacency with another router? chooses the best path builds the topology table executes the SPF algorithm exchanges link-state advertisements

exchanges link-state advertisements

Which step in the link-state routing process is described by a router flooding link-state and cost information about each directly connected link? exchanging link-state advertisements building the topology table injecting the default route selecting the router ID

exchanging link-state advertisements

Which step in the link-state routing process is described by a router running an algorithm to determine the best path to each destination? executing the SPF algorithm choosing the best route load balancing equal-cost paths declaring a neighbor to be inaccessible

executing the SPF algorithm

To establish a neighbor adjacency two OSPF routers will exchange hello packets. Which two values in the hello packets must match on both routers? (Choose two.) router ID hello interval dead interval router priority list of neighbors

hello interval dead interval

What indicates to a link-state router that a neighbor is unreachable? if the router no longer receives routing updates if the router no longer receives hello packets if the router receives an update with a hop count of 16 if the router receives an LSP with previously learned information

if the router no longer receives hello packets

Which OSPF data structure is identical on all OSPF routers that share the same area? adjacency database link-state database routing table forwarding database

link-state database

An OSPF router has three directly connected networks; 172.16.0.0/16, 172.16.1.0/16, and 172.16.2.0/16. Which OSPF network command would advertise only the 172.16.1.0 network to neighbors? router(config-router)# network 172.16.1.0 0.0.255.255 area 0 router(config-router)# network 172.16.0.0 0.0.15.255 area 0 router(config-router)# network 172.16.1.0 255.255.255.0 area 0 router(config-router)# network 172.16.1.0 0.0.0.0 area 0

router(config-router)# network 172.16.1.0 255.255.255.0 area 0

Which command will a network engineer issue to verify the configured hello and dead timer intervals on a point-to-point WAN link between two routers that are running OSPFv2? show ip ospf neighbor show ip ospf interface serial 0/0/0 show ipv6 ospf interface serial 0/0/0 show ip ospf interface fastethernet 0/1

show ip ospf interface serial 0/0/0

What command would be used to determine if a routing protocol-initiated relationship had been made with an adjacent router? ping show ip protocols show ip ospf neighbor show ip interface brief

show ip ospf neighbor

Which command is used to verify that OSPF is enabled and also provides a list of the networks that are being advertised by the network?​ show ip protocols show ip ospf interface show ip interface brief show ip route ospf

show ip protocols

A network technician issues the following commands when configuring a router: R1(config)# router ospf 11 R1(config-router)# network 10.10.10.0 0.0.0.255 area 0 What does the number 11 represent? the autonomous system number to which R1 belongs the area number where R1 is located the cost of the link to R1 the OSPF process ID on R1 the administrative distance that is manually assigned to R1

the OSPF process ID on R1

What is used to facilitate hierarchical routing in OSPF? autosummarization the use of multiple areas frequent SPF calculations the election of designated routers

the use of multiple areas

What is the reason for a network engineer to alter the default reference bandwidth parameter when configuring OSPF? to more accurately reflect the cost of links greater than 100 Mb/s to increase the speed of the link to force that specific link to be used in the destination route to enable the link for OSPF routing

to more accurately reflect the cost of links greater than 100 Mb/s

What are the two purposes of an OSPF router ID? (Choose two.) to facilitate the establishment of network convergence to uniquely identify the router within the OSPF domain to facilitate the transition of the OSPF neighbor state to Full to facilitate router participation in the election of the designated router to enable the SPF algorithm to determine the lowest cost path to remote networks

to uniquely identify the router within the OSPF domain to facilitate router participation in the election of the designated router