Practice Free H12-831_V1.0-ENU Exam Online Questions
In the network shown in the figure, R1, R2, R4, and R5 run IS-IS, and the area number is 49.0001. R3 and R6 run IS-IS, and the area number is 49.0002. Inside AS65000, R1, R3, R4, and R6 all establish IBGP neighbor relationships with R2 and R5, of which R2 and R5 are RRs and R1, R4, R3, and R6 are clients. IBGP neighbor relationships are all established using the Loopback0 interface. The IP address of the Loopback0 interface of each device is 10.0.X.X/32, and the Router ID is 10.0.X.X, where X is the device number. R1 and R4 introduce the external network 192.168.1.0/24 into BGP through the import method, and R3 and R6 introduce the external network 192.168.2.0/24 into BGP through the import method.
By default, which of the following descriptions are correct? (Multiple choice)
- A . For 192.168.1.0/24, the Originator_ID attribute carried by R2’s preferred BGP route is 10.0.1.1
- B . For 192.168.1.0/24, the Originator_ID attribute carried by R6’s preferred BGP route is 10.0.1.1
- C . For 192.168.1.0/24, R5 prefers the route received from R1
- D . For 192.168.1.0/24, the Originator_ID attribute carried by R3’s preferred BGP route is 10.0.2.2
As shown in the figure, CE1 sends VPN1 traffic to PE1. After receiving it, PE1 will forward the VPN traffic.
Which of the following descriptions of this scenario are correct? (Multiple choice)
- A . The interface on which PE1 receives the data is bound to the VPN1 instance.
- B . PE1 will use the LDP label corresponding to the Next_Hop address of the VPNv4 route as the outer label of the label message
- C . PE1 will check the forwarding table corresponding to the VPN1 instance and obtain the Tunnel ID information
- D . PE1 will search for the corresponding private network label according to Tunnel 1D and push the label header into the message.
On the IS-IS IPv6 network shown in the figure, after the network becomes stable:
R1 can ping 2000:12::0, and the display ipv6 neighbors command can be used to display the MAC address corresponding to 2000:12::0.
Is this statement TRUE or FALSE?
- A . TRUE
- B . FALSE
B
Explanation:
Comprehensive and Detailed In-Depth
Understanding the IPv6 Addressing and IS-IS Network
IPv6 Addressing in the Figure:
R1 has the address: 2000:12::1/64
R2 has the address: 2000:12::0/127
The link between them is using a /127 subnet (2000:12::0/127).
Behavior of IPv6 /127 Subnet Mask
In IPv6, a /127 prefix is commonly used on point-to-point links to avoid the issue of subnet-router anycast (::0).
RFC 6164 recommends using /127 instead of /64 for point-to-point links to reduce unnecessary anycast behavior.
2000:12::0 is the network address (first address in the subnet) and is not assigned to an interface.
Analyzing the Two Statements in the Question
Statement 1: "R1 can ping 2000:12::0" ❌ (Incorrect)
In IPv6, the first address (::0) in a /127 subnet is typically reserved as a network address and not assigned to any router.
R1 cannot ping 2000:12::0 because it is not assigned to R2 as an active IP.
Correct ping targets would be:
R1 pinging R2’s actual address (2000:12::1 or 2000:12::2 depending on numbering).
Statement 2: "display ipv6 neighbors command can be used to display the MAC address corresponding to 2000:12::0" ❌ (Incorrect)
The display ipv6 neighbors command is used to show the MAC address of an active neighbor (i.e., a reachable device).
Since 2000:12::0 is not assigned to a specific router, it will not have a MAC address in the neighbor table.
Final Conclusion:
❌ R1 cannot ping 2000:12::0 because it is the network address in a /127 subnet.
❌ The display ipv6 neighbors command cannot show a MAC address for 2000:12::0 because it is not assigned to a router.
Thus, the correct answer is: B. FALSE.
Reference:
HCIP-Datacom-Advanced Routing & Switching Technology V1.0 C IPv6 Addressing and IS-IS for IPv6
Huawei Official HCIP-Datacom Study Guide C IPv6 Neighbor Discovery and Point-to-Point Links
RFC 6164 C Using 127-Bit IPv6 Prefixes on Inter-Router Links
In the IS-IS network shown in the figure, R1 introduces the default route through the "default-route-advertise always level-1" command, and R2 introduces the default route through the "default-route-advertise always level-2" command.
Which of the following routers have default routes in their routing tables?
- A . R3
- B . R4
- C . R2
- D . R1
An interface of the switch is in error-down state, probably because the average rate of broadcast packets received by the interface exceeds the maximum threshold set by the administrator in storm control.
- A . True
- B . False
In order to support multi-topology functions, which of the following TLVs has been newly added by IS-IS?
- A . TLV No. 229
- B . TLV No. 236
- C . TLV No. 129
- D . TLV No. 232
The Router-LSA generated by a router is shown in the figure.
Based on this LSA, which of the following descriptions are correct? (Multiple choice)
- A . At least one interface of the router belongs to the NSSA area
- B . The router is an ASBR
- C . At least one interface of the router belongs to area 0
- D . The router is an ABR
In the OSPFv3 network shown in the figure, area 1 is a stub area, area 2 is a normal area, and area 3 is an NSSA area.
Which of the following types of LSAs will only appear in area 2?
- A . AS-External-LSA
- B . Router-LSA
- C . Link-LSA
- D . Intra-Area-Prefix-LSA
In a certain MPLS network, the LSP information of R1 and R3 is shown in the figure. At this time, the administrator enters the command ping -a 1.1.1.1 3.3.3.3 on R1.
Which of the following descriptions of this scenario is correct?
- A . The Echo Request message received by R2 carries label 1025, while the Echo Reply message received by R2 does not carry a label.
- B . The Echo Request message received by R2 carries label 1025, and the Echo Reply message received by R2 carries label 1024
- C . The Echo Request message received by R2 does not carry a label, and the Echo Reply message received by R2 does not carry a label either.
- D . The Echo Request message received by R2 does not carry a label, and the Echo Reply message received by R2 carries label 1024
The equipment operating environment refers to the external environment such as the equipment room, power supply, and heat dissipation where the equipment operates. This is the basic condition for the equipment to operate. For the maintenance of the equipment operating environment, the staff can only complete it by visiting the site in person.
- A . True
- B . False