CCNA2 - Examen 7习题答案

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CCNA2 -
Examen 7

1.-
Which
of the following can exist in a distance vector network that has not converged?
(Choose three.)
routing loops
inconsistent traffic forwarding
no
traffic forwarding until system converges
inconsistent routing table entries
routing
table updates sent to wrong
destinations

2.-
The
graphic shows a network that is configured to use RIP routing protocol. Router2
detects that the link to Router1 has gone down. It then advertises the network
for this link with a hop count metric of 16. Which routing loop prevention mechanism is in effect?
split horizon
error condition
hold-down timer
route poisoning
count to infinity

3.-
When
a routing table update is received by a router in a
distance vector network, which of the following
occurs?
The
hop count metrics for the enclosed routes are
incremented.
The
update is forwarded to the gateway router for
verification.
Path
entries are checked for routing loops.
The
hop count metrics for the enclosed routes are
decremented.
Static
routes are updated with the new
information.

4.-
Which
of the following methods does split horizon use to reduce incorrect routing
information?
Routing
updates are split in half to reduce the update
time.
Information
learned from one source is not distributed back to that
source.
New
route information must be learned from multiple sources to be
accepted.
The
time between updates is split in half to speed
convergence.
New
route information is suppressed until the system has
converged.

5.—
When
does a distance vector routing protocol set a hold-down timer on a
route?
when
the metric value of the route decreases
when
the route is marked as inaccessible
when
the metric value for the route improves
when
a regular update is received from a neighboring
router

6.-
Which
of the following functions are performed by a router as routing information
travels through the network? (Choose two.)
advertise supported applications
identify new destinations
calculate packet speed
verify network scalability
identify invalid networks

7.-
Which
of the following routes within an autonomous system does not include subnet
information?
interior routes
system routes
border routes
exterior routes

8.-
Which
of the following is a correct IGRP configuration for the routers shown in the
network diagram?
RouterA(config)# router igrp
RouterA(config-router)# network
192.168.0.0
RouterB(config)# router igrp 101
RouterB(config-router)# network
192.168.0.0
RouterA(config)# router igrp 45
RouterA(config-router)# network 192.168.1.0
RouterA(config-router)# network
192.168.2.0
RouterB(config)# router igrp 1
RouterB(config-router)# network 192.168.1.0
RouterB(config-router)# network
192.168.2.0
RouterA(config)# router igrp 1
RouterA(config-router)# network 192.168.2.0
RouterA(config-router)# network
192.168.3.0
RouterB(config)# router igrp 45
RouterB(config-router)# network 192.168.1.0
RouterB(config-router)# network
192.168.2.0


10.-
The
command show ip protocols was just issued and the following
line was displayed in the output:
Gateway 192.168.2.1 Distance 100
Last Update 00:00:54

When
should the next routing table update be received assuming the configuration uses
default values?
6 seconds
24 seconds
30 seconds
36 seconds
90 seconds


9.-
What
actions will occur after RouterA loses connectivity to
network 114.125.16.0? (Choose two.)
RouterB
will include network 123.92.76.0 and 136.125.85.0 in its update to RouterA.
During
the next update interval, RouterB will send a RIP
update out both ports that includes the inaccessible
network.
During
the next update interval, RouterC will send an update
to RouterB stating that network 114.125.16.0 is
accessible in 2 hops.
Router
C will learn of the loss of connectivity to network 114.125.16.0 from RouterB.
RouterB
will include network 123.92.76.0 and 136.125.85.0 in its update to RouterC.

11.-
Which
command set will stop the IGRP routing process?
RouterB(config)# router igrp
101
RouterB(config-router)#shutdown
RouterB(config)# router igrp
101
RouterB(config-router)#network no
192.168.2.0
RouterB(config)# no router igrp
101
RouterB(config)# router no igrp
101

12.-
Refer
to the graphic. Assuming default settings are configured, which routing protocol
has been configured on the router?
OSPF
RIP
IGRP
BGP
Static

13.-
The
following line was displayed in the output of the show ip route command:
192.168.3.0/24 [100/80135]
via 192.168.2.2, 00:00:30,
Serial0/0
What
is the administrative distance of the routing protocol
enabled?
30
80
100
135
80135

14.-
The
following line was displayed in the output of the show ip route command:
192.168.3.0/24 [100/80135]
via 192.168.2.2, 00:00:30,
Serial0/0
Based
on this information, which routing protocol is
enabled?
IP
RIP
IGRP
IGP
OSPF

15.-
Which
of the following would be the correct command sequence to enable RIP on Router B
for all connected networks?
RouterB#
router rip
RouterB(router)# network
210.36.7.0
RouterB(router)# network
220.17.29.0
RouterB(router)# network
211.168.74.0
RouterB(config)# router rip
RouterB(config-router)# network
198.16.4.0
RouterB(config-router)# network 211.168.74.0
RouterB(config-router)# network
199.84.32.0
RouterB(config)# configure router rip
RouterB(config-router)# network
210.36.7.0
RouterB(config-router)# network 199.84.32.0
RouterB(config-router)# network
211.168.74.0
RouterB(config)# router rip
RouterB(config-router)# network
198.16.4.0
RouterB(config-router)# network 210.36.7.0
RouterB(config-router)# network
211.168.74.0
RouterB(config)# router rip
RouterB(config-router)# network
198.16.4.0
RouterB(config-router)# network 210.36.7.0
RouterB(config-router)# network
220.17.29.0

16.-
Three
routers running RIP are connected in a mesh configuration. Which command could
be issued by a network administrator to decrease convergence time on this
network? (Choose two.)
Router(config-router)# update-timer
40
Router(config-router)# update-timer
25
Router(config-router)# holdown-timer
120
Router(config-router)# holdown-timer 90


17.-
Which
command will help to conserve bandwidth on a network running
RIP?
Router(config-router)# update-timer
25
Router(config-router)# update-timer
40
Router(config-router)# holdown-timer
96
Router(config-router)# holdown-timer
150

18.-
The
administrator of the network depicted in the graphic would like to decrease the
network's convergence time. How can this be accomplished?
disable
split horizon on the routers
increase
the update interval on the routers
change
the RIP holddown timer to 96
seconds
change
the RIP holddown timer to 126
seconds

19.-
Router
B received an interface configuration change. Suddenly, it transmits a new
update. Which of the following could have triggered this update? (Choose
two.)
Router
B received a configuration change.
Router
A sent a message requesting an update.
Router
C came online after Router B sent the RIP
update.
Router
B received an error message indicating the last update was not
received.

20.-
Which
command will display RIP activity as it occurs on a
router?
debug ip rip
show ip route
show ip interface
show ip protocols
debug ip rip config
show ip rip database

21.-
How
would an administrator configure a static route for use if a primary route
failed?
configure
the route with a metric greater than the default
value
configure
the route and the router will activate it as
needed
configure
the route to activate by using the redistribute static
command
configure
the route with an administrative distance greater than the default
value

22.-
A
router has several classful networks in its routing
table. If the router receives packets for a subnet that is not in its routing
table and the ip classless command is
disabled but a default route is defined, what will happen to the
packets?
The
packets will be forwarded using the default
route.
The
packets will be forwarded using a route for one of the major
networks.
A
nonreachable message will be returned to the
source.
The
packets will be discarded.
A
default route will be developed by the
router.

23.-
Router
D sends an update to both Router A and Router C about Network 5. If RIP is the
routing protocol, how would the split horizon rule affect how Router A sends
updates?
Router
A would updates about Network 5 to all routers on the
network.
Router
A would send updates about Network 5 to both Router B and Router
D.
Router
A would send updates about Network 5 to Router B but not to Router
D.
Router
A would send updates about Network 5 to Router D but not to Router
B.
               
               
               

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