CCNA 3 Chapter 7 v6 Exam Answers

Refer to the exhibit. Router R3 is receiving multiple routes through the EIGRP routing protocol. Which statement is true about the implementation of summarization in this network?

Automatic summarization is disabled on R3, so no routes to the null0 interface have been created for networks 172.21.0.0/16 and 192168.254.0/24. If automatic summarization had been enabled on R3 neighbors, the networks that were received by R3 would have been summarized classful statements.

Refer to the exhibit. Which two routes will be advertised to the router ISP if autosummarization is disabled? (Choose two.)

If the no auto-summary command was issued disabling the autosummarization, all subnetworks will be advertised, without summarization.

What is the default maximum amount of bandwidth that can be used for exchanging EIGRP messages on an EIGRP-configured interface?

What is the purpose of a Null0 route in the routing table?

Refer to the exhibit. After the configuration shown is applied on router R1, the exhibited status message is displayed. Router R1 is unable to form a neighbor relationship with R2 on the serial 0/1/0 interface. What is the most likely cause of this problem?

According to the status message, serial 0/1/0 is receiving EIGRP packets coming from the IPv4 address 192.168.254.9. This IPv4 address is on a different subnet in contrast to the IP address configured on serial 0/1/0 of R1. The passive-interface command would have prevented any neighbor relationship from forming if the command was issued on serial 0/1/0. Changing the hello interval on one router and not another will not cause an EIGRP neighbor relationship to fail.

By default, how many equal-cost routes to the same destination network will EIGRP install in the routing table?

For load balancing, EIGRP will by default install up to four equal-cost paths to the same destination network in the routing table.

Which routing protocol supports unequal-cost load balancing on Cisco routers?

EIGRP is unique because of its support of unequal-cost load balancing.

Which two steps must be taken in order to send a default route to other EIGRP routers? (Choose two.)

Any router can have a default route (quad zero route) configured. In order to propagate a default route down to other EIGRP routers, the redistribute static command is used to include the configured default route in EIGRP updates.

Which command can be issued on a router to verify that automatic summarization is enabled?

Refer to the exhibit. Considering that R2, R3, and R4 are correctly configured, why did R1 not establish an adjacency with R2, R3, and R4?

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Refer to the exhibit. Remote users are experiencing connectivity problems when attempting to reach hosts in the 172.21.100.0 /24 network. Using the output in the exhibit, what is the most likely cause of the connectivity problem?

When enabling EIGRP, the network command must be applied to the classful network address of the interface or to a subnet with the appropriate wildcard mask. The network 172.20.0.0 will only activate interfaces in that network. The wildcard mask 0.1.255.255 must be issued to support both 172.20.0.0 and 172.21.0.0 in a single network statement.

Refer to the exhibit. Routers R1 and R2 are directly connected via their serial interfaces and are both running the EIGRP routing protocol. R1 and R2 can ping the directly connected serial interface of their neighbor, but they cannot form an EIGRP neighbor adjacency. What action should be taken to solve this problem?

In EIGRP configuration, the command that starts the EIGRP process is followed by a number that is the autonomous system (AS) number, router eigrp as-number. The as-number must be the same in all routers that are in the same EIGRP routing domain. In this case R2 is configured with AS 80 and R1 is configured with AS 50.

Open the PT Activity. Perform the tasks in the activity instructions and then answer the question.
R1 and R2 could not establish an EIGRP adjacency. What is the problem?​

The IPv6 EIGRP process is down on R1 as can be seen:

R1# show ipv6 eigrp interfaces
IPv6-EIGRP interfaces for process 1
% EIGRP 1 is in SHUTDOWN
R1#

The administrator must issue the no shutdown command on the IPv6 router configuration mode.

Which statement is supported by the output?

When a Cisco router is configured with fast-switching, how are packets distributed over equal-cost paths?

Fill in the blank. Do not use abbreviations.The command to propagate the default route from the router Border to the rest of the EIGRP domain is Border(config-router)#

One way to propagate the default route to the rest of the EIGRP domain is to use the command redistribute static in the router eigrp (config-router)# mode.

Which three statements are advantages of using automatic summarization? (Choose three.)

Automatic summarization minimizes the number of routes in the routing table. It reduces the frequency of routing updates. A disadvantage of automatic summarization is that it can create reachability problems in discontiguous networks.

Two routers, R1 and R2, share a 64 kb/s link. An administrator wants to limit the bandwidth used by EIGRP between these two routers to 48 kb/s. Which command is used on both routers to configure the new bandwidth setting?

Refer to the exhibit. An administrator wants EIGRP on Router1 to load balance traffic to network 2001:db8:11:10::/64 across two interfaces. Currently traffic is using only interface GigabitEthernet0/1. A second route, not in the routing table, is available with a metric of 264000. What value is needed in the variance command to make EIGRP put the second route into the routing table?

A variance of 11 is needed to load balance across the second route. The metric of the existing successor route is 25000. The metric of the second route is 264000. The first metric needs to be multiplied by 11, which is 275000, in order for the route to be put into the routing table.

Refer to the exhibit. Which two conclusions can be drawn from the exhibited configuration? (Choose two.)

The configuration supports unequal-cost load balancing as shown by the variance value of 3. The default variance for EIGRP is 1. The no auto-summary command is needed to prevent autosummarization.

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Refer to the exhibit. All networks are active in the same EIGRP routing domain. When the auto-summary command is issued on R3, which two summary networks will be calculated on R3? (Choose two.)

As a result of implementing EIGRP automatic summarization, router R3 uses a classful network addressing scheme to group networks together based on their classful network mask. 192.168.10.4/30 and 192.168.10.8/30 are shortened to 192.168.10.0/24 and 172.16.3.0/24 is summarized to 172.16.0.0/16. 192.168.1.0/24 is already using its classful mask and is not summarized.

What is the administrative distance of externally learned EIGRP routes?

Assuming that EIGRP is enabled on both routers and automatic summarization is enabled, what must be configured to ensure that R1 will be able to reach the 2.2.2.0/24 network?

The networks 2.1.1.0/24 and 2.2.2.0/24 are two subnets of the Class A network 2.0.0.0/8. When automatic summarization is enabled, EIGRP will summarize and advertise networks at the major network boundary. In this case, both routers will advertise the network 2.0.0.0/8, which will cause failure of connectivity.

In which scenario will the use of EIGRP automatic summarization cause inconsistent routing in a network?

If there are discontiguous IPv4 networks, automatic summarization causes inconsistent routing because routes are summarized at classful boundaries. When there is no common subnet between EIGRP neighbors, an adjacency cannot form. Mismatching EIGRP AS numbers and the lack of an adjacency will not cause inconsistent routing, but a lack of routing overall.

Fill in the blank. Do not use abbreviations.
The ___ command causes an EIGRP router to stop sending hello packets through an interface.

The passive-interface command prevents routing updates and hello packets from traveling through an interface.