- Home
- Networking
- CCNA Routing and Switching 200-105
116.
An enterprise uses a dual-stack model of deployment for IPv4 and IPv6, using OSPF
as the routing protocol for both. Router R1 has IPv4 and IPv6 addresses on its G0/0
and S0/0/0 interfaces only, with OSPFv2 and OSPFv3 enabled on both interfaces for
area 0 and the router ID explicitly set for both protocols. Comparing the OSPFv2 and
OSPFv3 configuration, which of the following statements is true?
- A.The OSPFv3 configuration, but not OSPFv2, uses the router-id router-id router subcommand.
- B.Both protocols use the router-id router-id router subcommand.
- C.Both protocols use the network network-number wildcard area area-id router subcommand.
- D.Both protocols use the ipv6 ospf process-id area area-id interface subcommand.
- Answer & Explanation
- Report
Answer : [B]
Explanation :
Explanation :
| The OSPFv3 configuration would use ipv6 router ospf process-id, router-id router-id, and then, under each interface, the ipv6 ospf process-id area area-id command. OSPFv2 uses the exact same syntax on the router-id command. Only OSPFv3 uses the ipv6 ospf process-id area area-id interface subcommand, and OSPFv3 does not use the network command. |
117.
R1 and R2 are routers that connect to the same VLAN. Which of the answers list an
item that can prevent the two routers from becoming OSPFv3 neighbors? (Choose
three answers.)
- A.Mismatched Hello timers
- B.Mismatched process IDs
- C.IPv6 addresses in different subnets
- D.Equal router IDs
- E.One passive router interface (used on this link)
- Answer & Explanation
- Report
Answer : [A, D and E]
Explanation :
Explanation :
| OSPFv3 uses the same rules as OSPFv2 in regard to all these items except the addresses; OSPFv3 does not require that the neighbors have IPv6 addresses in the same subnet. Mismatched Hello timers prevents neighbor relationships, as do duplicate router IDs. Also, neither can have its interface set to passive; otherwise, the neighbor relationship fails to complete. The PIDs can be different or the same because they are not checked as part of the choice to become neighbors. |
118.
The example shows an excerpt from the show ipv6 route ospf command on a router
(R1). Which of the answers are correct about the interpretation of the meaning of the
output of this command? (Choose two answers.)
R1# show ipv6 route ospf
OI 2001:DB8:1:4::/64 [110/129]
via FE80::FF:FE00:1, Serial0/0/1
- A.110 is the metric for the route.
- B.S0/0/1 is an interface on R1.
- C.FE80::FF:FE00:1 is a link-local address on R1.
- D.OI means that the route is an interarea OSPF route.
- Answer & Explanation
- Report
Answer : [B and D]
Explanation :
Explanation :
| The second line lists the forwarding instructions for the route, specifically the link-local address of the neighboring router and the local router’s outgoing interface. These facts identify one correct and one incorrect answer. The OI code indeed means OSPF and interarea; intra-area routes simply omit the I. In brackets, the first number is the administrative distance, and the second number (129 in this case) is the metric. |
119.
Router R1 has been configured as a dual-stack IPv4/IPv6 router, using interfaces
S0/0/0, S0/0/1, and GigabitEthernet0/1. As a new engineer hired at the company, you
do not know whether any of the interfaces are passive. Which of the following commands lets you find whether G0/1 is passive, either by the command listing that fact
or by that command leaving passive interfaces out of its list of interfaces?
- A.show ipv6 ospf interface brief
- B.show ipv6 protocols
- C.show ipv6 ospf interface G0/1
- D.show ipv6 ospf interface passive
- Answer & Explanation
- Report
Answer : [C]
Explanation :
Explanation :
| The correct answer lists detailed information about OSPFv3 related to interface G0/1, including a notation that the interface is passive (if it is). Of the incorrect answers, in the show ipv6 ospf interface passive command, the passive keyword does not exist. The other two commands list all OSPFv3-enabled interfaces on the router, but the list includes passive interfaces, with no notation about which are passive and which are not. |
120.
An enterprise uses a dual-stack model of deployment for IPv4 and IPv6, using EIGRP
as the routing protocol for both. Router R1 has IPv4 and IPv6 addresses on its G0/0
and S0/0/0 interfaces only, with EIGRP for IPv4 and EIGRP for IPv6 enabled on both
interfaces. Which of the following answers is a valid way to configure R1 so that it
enables EIGRP for IPv6 on the exact same interfaces as EIGRP for IPv4 in this case?
- A.Adding the dual-stack all-interfaces router subcommand for EIGRP for IPv6
- B.Adding the dual-stack interface subcommand to interfaces G0/0 and S0/0/0
- C.Adding the ipv6 eigrp asn interface subcommand to interfaces G0/0 and S0/0/0
- D.Adding the dual-stack all-interfaces router subcommand for EIGRP for IPv4
- Answer & Explanation
- Report
Answer : [C]
Explanation :
Explanation :
| IOS supports no direct method for IOS to decide which interfaces have EIGRP for IPv4 enabled, and then automatically enable EIGRP for IPv6 on those same interfaces. The correct answer shows how to enable EIGRP for IPv6 directly on the two interfaces in question. The three incorrect answers also list nonexistent commands. |
|
|
||||||||||||||||||||||||||||
