In the network shown in the figure, OSPF protocol is run between R1, R2, and R3 . IBGP neighbor relationship is established between R1 and R3 using loopback interface. If OSPF is disabled on R2’s GE0/0/1 interface through the "undo network xxxx yyyy" command, and BGP neighbor relationship is checked on R1, by default, the longest time for R1’s BGP neighbor relationship to change from Up state to Down state is which of the following?
- A . 180s
- B . 10s
- C . 40s
- D . 60s
In the network shown in the figure, OSPF protocol is running between R1, R2, and R3, and OSPF BFD feature is enabled. IBGP neighbor relationship is established between R1 and R3 using loopback interface. If GE0/0/1 interface of R2 is shut down, and BGP neighbor relationship is checked on R1, by default, which of the following is the longest time for R1 BGP neighbor relationship to change from Up state to Down state?
- A . 180s
- B . 40s
- C . 60s
- D . 3s
In the network shown in the figure, OSPF runs between R1, R2, and R3. R1 and R3 use the loopback interface to establish an IBGP neighbor relationship, and the BFD function is enabled in the BGP process. The BFD parameters are "bfd min-tx-interval 1000 min-rx-interval 1000 detect-multiplier 6". If OSPF is disabled on R2’s GE0/0/1 interface through the "undo network xxxx yyyy" command, and the BGP neighbor relationship is checked on R1, by default, the longest time for the R1 BGP neighbor relationship to change from Up to Down is which of the following?
- A . 180s
- B . 6s
- C . 40s
- D . 60s
Which of the following is not included in the OSPF Hello message?
- A . Router ID
- B . Process ID
- C . Area ID
- D . Network Mask
A large Internet service provider needs to shut down the equipment in the computer room for maintenance in batches. As a cutover project manager, which of the following time points would you prefer?
- A . Labor Day
- B . National Day
- C . Weekend
- D . Working Days
By default, the cost type of IS-IS routes is narrow mode. In this mode, the maximum value of the route cost is which of the following?
- A . 16777215
- B . 65535
- C . 63
- D . 1023
Which of the following commands can be configured on an IS-IS Level-1-2 device to prevent the Level-1 device from generating a default route?
- A . attached-bit advertise never
- B . attached-bit advertise always
- C . import-route isis level-2 into level-1
- D . attached-bit avoid-learning
When an OSPFv3 message is encapsulated in an IPv6 message, which of the following is the value of the Next Header field in the IPv6 message header?
- A . 6
- B . 189
- C . 89
- D . 17
By default, the IS-IS LSP refresh interval is which of the following?
- A . 1200s
- B . 900s
- C . 3600s
- D . 10s
The "set-overload" command is configured in the process of an IS-IS router. By default, how long does it take for the router to exit the overload state after restarting?
- A . 900s
- B . 600s
- C . 500s
- D . 1200s
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
Which of the following is not a new addition to IS-IS to support IPv6 routing processing and calculation?
- A . TLV 236: describes the reachability of the network by defining routing information prefix, metric value and other information
- B . TLV 232: It is equivalent to the "IP Interface Address" TLV in IPv4, except that the original 32-bit IPv4 address is changed to a 128-bit IPv6 address
- C . When an IPv6 route is advertised externally, the NLPID value must be included
- D . The source IP address of the IS-IS Hello message is changed to the link-local address
In order to support the processing and calculation of IPv6 routes, IS-IS adds a new NLPID in TLV No. 129. NLPID is an 8-bit field that identifies the network layer protocol message. Which of the following is the NLPID value of IPv6?
- A . 232
- B . 236
- C . 142
- D . 204
There are many types of MAC address entries on the switch. Which of the following types of entries can discard messages by matching the source and destination MAC addresses of received messages, thereby filtering out illegal users?
- A . Business MAC address table
- B . Dynamic MAC address table
- C . Static MAC address table
- D . Blackhole MAC address table
The MPLS architecture is divided into a control plane and a forwarding plane, which contains multiple protocols and tables. Which of the following tables is responsible for forwarding packets with MPLS labels?
- A . Label Information Table LIB
- B . Label Forwarding Information Table LFIB
- C . Forwarding Information Table FIB
- D . Routing Information Table RIB
In the network shown in the figure, R1 and R2 establish an EBGP neighbor relationship through a direct interface, and the BFD function is enabled in the BGP process. The BFD parameters are "bfd min-tx-interval 1000 min-rx-interval 1000 detect-multiplier 6". If the IP address of GE0/0/0 on R2 is deleted and the BGP neighbor relationship is checked on R1, which of the following is the longest time for the BGP neighbor relationship on R1 to change from Up to Down?
- A . 0s
- B . 60s
- C . 6s
- D . 180s
If an OSPF router is set as a stub router, which of the following is the link metric in the LSA sent by the router?
- A . 1
- B . 100
- C . 65535
- D . 10
In a BGP/MPLS IP VPN network, VPNv4 routing transfers carry Export RT values. Which of the following path attributes does MP-BGP use to carry Export RT?
- A . AS_Path
- B . Extended_Community
- C . MP_REACH_NLRI
- D . Local_Preference
In a BGP/MPLS IP VPN network, VPNv4 routing transfers carry RD values. Which of the following path attributes does MP-BGP use to carry the RD value?
- A . Extended_Community
- B . AS_Path
- C . MP_REACH_NLR
- D . Local_Preference
When traffic accesses the backbone network, VPN isolation is required. At this time, the interface configuration of a PE router is as follows. If the administrator needs to bind the interface to VPN1 and the interface IP address remains unchanged, which of the following descriptions of the administrator’s operation is correct?
Interface GigabitEthernet 0/0/1
IP address 192.168.100.2 24
- A . After the administrator enters the command ip binding vpn-instance VPN1 in the interface view, it is also necessary to bind the RD value of VPN1
- B . After the administrator types the command ip binding vpn-instance VPN1 in the interface view, he needs to bind the RT value of VPN1.
- C . After the administrator enters the command ip binding vpn-instance VPN1 in the interface view, he needs to reconfigure the interface IP address
- D . The administrator can type the command ip binding vpn-instance VPN1 in the interface view.
In the BGP/MPLS IP VPN network shown in the figure, the administrator uses Hub-spoke networking to implement centralized control of VPN traffic at the Hub site. Which of the following RT value plans for each device is correct?
- A . PE1 VPN1: IRT=100:1; ERT=100:1
PE2 VPN1: IRT=100:1; ERT=100:1
PE3 VPN1: IRT=100:1; ERT=100:1 - B . PE1 VPN1: IRT=100:1; ERT=200:1
PE2 VPN1: IRT=100:1; ERT=200:1
PE3 VPN_in: IRT=100:1; VPN_out: ERT=200:1 - C . PE1 VPN1: IRT=100:1; ERT=200:1
PE2 VPN1: IRT=100:1; ERT=200:1
PE3 VPN1: IRT=200:1; ERT=100:1 - D . PE1 VPN1: IRT=100:1; ERT=200:1
PE2 VPN1: IRT=100:1; ERT=200:1
PE3 VPN_in: IRT=200:1; VPN_out: ERT=100:1
In the Hub&Spoke network shown in the figure, in order to achieve correct routing transmission, the administrator must manually configure which of the following commands on the Hub-PE?
- A . [Hub-PE-bgp-VPN_in] peer xxxx allow-as-loop
- B . [Hub-PE-bgp-VPN_in] peer xxxx soo 200:1
- C . [Hub-PE-bgp-VPN_out] peer xxxx soo 200:1
- D . [Hub-PE-bgp-VPN_out] peer xxxx allow-as-loop
In a Hub & Spoke network, the route transfer path of VPN1 is shown in the figure. When Hub-PE forwards the VPN1 route to Spoke PE2, which of the following AS_Path is carried?
- A . A. S_Path is empty
- B . A. S_Path=100
- C . A. S_Path=65001, 100
- D . A. S_Path=65001, 100, 65002
The service routes of an enterprise are transmitted in the network. The partial configurations of PE1 and PE2 are shown in the figure. At this time, CE1 adds a new service network segment and announces it to Area 1 of OSPF 10. In this scenario, which type of LSA will CE2 receive, which will contain the service network segment newly announced by CE1?
- A . Type 5 LSA
- B . Type 1 LSA
- C . Type 2 LSA
- D . Type 3 LSA
In a BGP/MPLS IP VPN network, when which of the following routing protocols is running between CE and PE, the PE device can perform route redistribution operations without BGP?
- A . BGP
- B . Static routing
- C . IS-IS
- D . OSPF
In an MPLS network, when a transit device receives an MPLS message and prepares to perform label exchange, it finds that the value of the label after exchange is 0. Which of the following operations will it perform at this time?
- A . Push label 0 into the outer label of the MPLS packet and forward the MPLS packet carrying two layers of labels to the next hop
- B . Exchange label 0 with the original label in the MPLS message and forward the message to the next hop
- C . Pop the label in the MPLS message and forward the message to the next hop
- D . Do not process the label and directly forward the message to the next hop
In an MPLS network, data is forwarded based on information such as FIB, NHLFE, and ILM. Which of the following options is mainly used for information association?
- A . Label output
- B . Tunnel ID
- C . Tag operation type
- D . FEC
A network engineer captured a multicast data frame whose destination MAC address is 01-00-5e-00-01-01. Based on this analysis, which of the following cannot be the destination IPv4 address?
- A . 224.0.0.1
- B . 224.0.1.1
- C . 239.128.1.1
- D . 225.0.1.1
NetEngine AR router functions as a DHCP server and can assign IP addresses to clients in the same network segment or in different network segments.
Which of the following reasons will not cause the client to be unable to obtain an IP address?
- A . The link between the client and the server is faulty
- B . The DHCP function is not enabled on the device
- C . There are no available IP addresses in the address pool to allocate
- D . IP address lease period is less than 24 hours
A network engineer accidentally deleted the IP address of an interface through the command line. If he wants to view the deleted IP address, which of the following information should he query?
- A . Debug information
- B . Log information
- C . Trap information
- D . SNMP agent information
A network engineer enters "dir" on the device and obtains the following file names. Which of the following is most likely to be the version file of the device?
- A . V300R022000SPC100.cfg
- B . startup yl.rdb
- C . Ca.cer
- D . V300R022C00SPC100.cc
Network engineers found that the multicast client could not receive multicast data correctly, so they suspected that the group address set by the multicast server was incorrect. Which of the following cannot be the group address?
- A . 232.0.0.18
- B . 233.0.0.2
- C . 224.0.0.1
- D . 224. 0.1.5
When a device is abnormal or fails, it will generate a variety of information. According to the severity or urgency of the information, the information is divided into 8 levels. Which of the following has the highest severity level?
- A . Informational
- B . Debugging
- C . Notification
- D . Warning
The detection mechanism of BFD is that two systems establish a BFD session and periodically send BFD control messages along the path between them. If one party does not receive the BFD control message within a specified time, it is considered that a fault has occurred on the path.
Which of the following reasons will not cause the BFD session to go Down?
- A . The session-name of the BFD session is inconsistent
- B . The message with UDP port number 4784 is rejected
- C . The outbound interface bound to the single-hop BFD session is physically faulty
- D . The remote identifier and local identifier of the BFD session do not match
When a network engineer processes a single-hop BFD session that is Down, which of the following operations does he or she not need to perform?
- A . Repeat the display bfd statistics session all command to view the statistics of the BFD session sent and received packets.
- B . If a static route is bound to a BFD session, run the display ip routing-table command to check whether the static route exists in the routing table.
- C . Ping the link between the BFD sessions to check whether forwarding is normal
- D . Run the display current-configuration configuration bfd command to check whether the local discriminator and remote discriminator at both ends of the BFD session match.
When a network device has any of the following faults, the network device will report an alarm message with OID 1.3.6.1.4.1.2011.5.25.155.31.3 (node name hwOspfv2IntraAreaRouteridConflict) to the network management server through SNMP?
- A . The OSPF neighbor flapping suppression status changes
- B . OSPF detects a conflict in the local link DRIP address
- C . OSPF detects a router ID conflict within the area
- D . The local device deletes the OSPF routes advertised by other devices
A network engineer discovered that a link failure alarm frequently appeared on the interface of a certain device. The interface is an Ethernet optical port. Which of the following commands can the network engineer use to check the transmit and receive optical power of the interface?
- A . display alarm all
- B . display pon-transceiver
- C . display transceiver
- D . display temperature
When the administrator deploys the traffic suppression function on the switch, in the VLAN view of the device, which of the following types of messages can be suppressed based on the bit rate?
- A . Unknown multicast message
- B . Broadcast message
- C . Known unicast message
- D . Unknown unicast message
In the network shown in the figure, adjacent routers use directly connected interfaces to establish EBGP neighbor relationships. The AS number is 6500X, where X is the router number. R1 and R4 both have static routes to 192.168.1.0/24, which are introduced into BGP through import. By default, in the routing table of R3, the AS_Path attribute carried by the route entry to 192.168.1.0/24 is which of the following?
- A . 65006, 65005, 65004, 65001
- B . 65002, 65005, 65004
- C . 65006, 65005, 65004
- D . 65002, 65001
In the network shown in the figure, adjacent routers use directly connected interfaces to establish EBGP neighbor relationships. The AS number is 6500X, where X is the router number. R1 and R4 both have static routes to 192.168.1.0/24, which are introduced into BGP through import. The maximum number of equal-cost routes configured for EBGP load sharing on R3 is 8.
By default, the number of equal-cost routes from R3 to 192.168.1.0/24 is which of the following?
- A . 2
- B . 8
- C . 1
- D . 3
In the network shown in the figure, adjacent routers use directly connected interfaces to establish EBGP neighbor relationships. The Router ID of each device is 10.0.XX, and the AS number is 6500X, where X is the router number. R1 and R4 both have static routes to 192.168.1.0/24, which are imported into BGP. R3 configures the "peer yyyy as-path-filter 1 import" command for all neighbors. Which of the following can enable R3 to select the longest AS-Path to 192.168.1.0/24?
- A . ip as-path-filter 1 permit.*
ip as-path-filter 1 deny 65001$
ip as-path-filter 1 deny ^65005 - B . ip as-path-filter 1 deny ^65002
ip as-path-filter 1 deny ^65005
ip as-path-filter 1 permit.* - C . ip as-path-filter 1 deny 65001$
ip as-path-filter 1 permit.* - D . ip as-path-filter 1 deny .*6500
ip as-path-filter 1 permit.*
In the network shown in the figure, adjacent routers use directly connected interfaces to establish EBGP neighbor relationships. The Router ID of each device is 10.0.XX, and the AS number is 6500X, where X is the router number. R1 and R4 both have static routes to 192.168.1.0/24, which are introduced into BGP through import.
By default, among the routes received by R6 regarding 192.168.1.0/24, which of the following has the longest AS_Path length?
- A . 3
- B . 4
- C . 2
- D . 1
In the network shown in the figure, adjacent routers use directly connected interfaces to establish EBGP neighbor relationships. The Router ID of each device is 10.0.XX, and the AS number is 6500X, where X is the router number. R1 and R4 both have static routes to 192.168.1.0/24, which are introduced into BGP through import.
If the "ageregate 192.168.1.0.16 detail-suppresed" command is configured on R1, which of the following is the traffic path from R3 to 192.168.1.0/24?
- A . R3-R2-R1
- B . R3-R5-R1
- C . RЗ-R6-R5-R1
- D . R3-R5-R4
In the network shown in the figure, adjacent routers use directly connected interfaces to establish EBGP neighbor relationships. The Router ID of each device is 10.0.XX, and the AS number is 6500X, where X is the router number. R1 and R4 both have static routes to 192.168.1.0/24, which are imported into BGP. R1 adds the Community attribute value (1:1) when sending routes to its neighbors. All routers in the network are enabled to pass community attributes. R3 is configured with a routing policy that refuses to receive routes with a community attribute value of 1:1. Which of the following is the traffic path for R3 to reach 192.168.1.0/24?
- A . R3-R5-R1
- B . R3-R2-R4
- C . R3 has no route to 192.168.1.0/24
- D . R3-R2-R1
In the network shown in the figure, adjacent routers use directly connected interfaces to establish EBGP neighbor relationships. The Router ID of each device is 10.0.0.X, and the AS number is 6500X, where X is the router number. R1 and R4 both have static routes to 192.168.1.0/24, which are imported into BGP. R1 adds the community attribute value (1:1) when sending routes to its neighbors. All routers in the network are enabled to pass community attributes. Which of the following can make the traffic path from R3 to 192.168.1.0/24 pass through R4?
- A . Configure the routing policy on R4 to reject routes with a community attribute value of 1:1.
- B . Configure a routing policy on R5 to reject routes with a community attribute value of 1:1.
- C . Configure a routing policy on R3 to reject routes with a community attribute value of 1:1.
- D . Configure a routing policy on R2 to reject routes with a community attribute value of 1:1.
As shown in the figure, this is an MPLS message with multiple layers of labels nested. Which of the following is the correct value of the S field at the three positions S1, S2, and S3?
- A . S1=2, S2=1, S3=0
- B . S1=1, S2=1, S3=0
- C . S1=3, S2=2, S3=1
- D . S1=0, S2=0, S3=1
In the network shown in the figure, the administrator first completes the routing configuration as shown in the options, and then enables MPLS and LDP functions on all devices and interconnected interfaces of R1-R3, so as to realize the traffic from PC1 to PC2 forwarding based on MPLS in the network.
Which of the following routing configuration options can achieve this function?
- A . # R1
Bgp 65000
Router-id 1.1.1.1
Peer 3.3.3.3 as-number 65000
Peer 3.3.3.3 connect-interface LoopBack 0network 10.1.1.024
# R3
Bgp 65000
Router-id 3.3.3.3
Peer 1.1.1.1 as-number 65000
Peer 1.1.1.1 connect-interface LoopBack 0network 10.3.3.024 - B . # R1
Ospf 1
Area 0
Network 1.1.1.10.0.0.0
Network 10.1.12.00.0.0.255bgp 65000
Router-id 1.1.1.1
Peer 3.3.3.3 as-number 65000
Peer 3.3.3.3 connect-interface LoopBack 0network 10.1.1.024
Ip ip-prefix 1 index 10 permit 10.3.3.024route recursive-lookup tunnel ip-prefix 1
# R2
Ospf 1
Area 0
Network 2.2.2.20.0.0.0
Network 10.1.12.00.0.0.255
Network 10.1.23.00.0.0.255
# R3
Ospf 1
Area 0
Network 3.3.3.30.0.0.0
Network 10.1.23.00.0.0.255bgp 65000
Router-id 3.3.3.3
Peer 1.1.1.1 as-number 65000
Peer 1.1.1.1 connect-interface LoopBack 0
Network 10.3.3.024
Ip ip-prefix 1 index 10 permit 10.1.1.024route recursive-lookup tunnel ip-prefix 1 - C . # R1
Ospf 1
Area 0
Network 1.1.1.10.0.0.0
Network 10.1.12.00.0.0.255
Network 10.1.1.00.0.0.255
# Ospf 1
Area 0
Network 2.2.2.20.0.0.0
Network 10.1.12.00.0.0.255
Network 10.1.23.00.0.0.255
# R3 Ospf 1
Area 0
Network 3.3.3.30.0.0.0
Network 10.1.23.00.0.0.255
Network 10.3.3.00.0.0.255 - D . # R1
Ospf 1
Area 0
Network 1.1.1.10.0.0.0
Network 10.1.12.00.0.0.255
# R2
Ospf 1
Area 0
Network 2.2.2.20.0.0.0
Network 10.1.12.00.0.0.255
Network 10.1.23.00.0.0.255
# R3
Ospf 1
Area O
Network 3.3.3.30.0.0.0
Network 10.1.23.00.0.0.255
In a certain MPLS network, the LSP information of R1 and R2 is shown in the figure. At this time, the administrator enters the command ping 3.3.3.3 on R1. Which of the following descriptions of this scenario is correct?
- A . The Ping message sent by R1 will carry label 1025. After receiving it, R2 will perform label exchange and forward it based on MPLS.
- B . The Ping message sent by R1 does not carry any label, but R2 will add a label after receiving it and forward it based on MPLS
- C . The Ping message sent by R1 will carry label 1025. After receiving it, R2 will remove the label and forward it based on IP.
- D . The Ping message sent by R1 does not carry any label. After receiving it, R2 will forward it based on IP.
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
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 10.1.12.13.3.3.3 on R1. Which of the following descriptions of this scenario is correct?
- A . The Echo Request message received by R2 carries label 1025, and the Echo Reply message received by R2 carries label 1024.
- B . The Echo Request message received by R2 does not carry a label, and the Echo Reply message received by R2 carries label 1024
- C . The Echo Request message received by R2 carries label 1025, while the Echo Reply message received by R2 does not carry a label.
- D . 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.