H12-261_V3.0 HCIE-Routing & Switching (Written) V3.0 Questions and Answers

Stacking + Link Aggregation

TRILL+MSTP

stack+MSTP

Link set + MSTP

ifTP-B>0 and TC-B<0, the packet is marked in green

ifTP-B<0 and TC-B<0, the message is marked in red

ifTP-B>0 and TC-B<0, the packet is marked in yellow

ifTP-B>0 and TC-B>0, the packet is marked green

In the NSSA area, filtering for external route import and advertisement can be configured on ASBR or ABR.

Filtering for three types of LSAs needs to be configured on ABRs between OSPF areas

Filter LSA based on interface, can filter in and out direction, except Grace All LS except LSAA

When calculating routes based on the link state database, use filter-policy import command, this filtering method only affects the routing entries in the routing table. plus, for OSPF the link state database has no effect

The interval for sending Hello packets is inconsistent.

The IP address masks of the interfaces are inconsistent.

The authentication passwords are inconsistent.

Area types are inconsistent

CIR=TC/BC

CIR=BE/TC

TC=CIR/BC

TC=BC/CIR

TRUE

FALSE

True

false

VXLAThe tunnel between the Layer 2 and Layer 3 gateways is an IPv4 network.

IPv6overVXLAN can solve the problem of insufficient IP address resources for terminal tenants.

IPv46 Over VLAN does not generate ND entries.

IPv46 over VXL AN means VXL AThe overlay network of N is an IPv6 network.

The sender announces the initial window size

The sender does not need to transmit the full window size of the message

TCPSliding window allows multiple packets to be sent before an acknowledgment is received

After the retransmission timer expires, the sender has not received the acknowledgment and will retransmit the unacknowledged data

The receiver needs to confirm the data packet of the sender

Sliding window size can only increase or stay the same

R1

R2

R3

R4

Type7

Type5

Type4

Type3

On an interface, RSTP does not age out BPDUs

after more than 6 seconds.

existAfter MaxAge times out

existHello after time out

existForward After Delay times out

bfdSession can be established, after negotiation 40ms

bfdSession can be established, after negotiation 30ma

bfdSession can be established. each at its own time interval

bfdSession could not be established

Type5 LSA

Type7 LSA

Type3 LSA

Type1 LSA

802.3z

802.3ab

802.3ad

802.3af

TRUE

FALSE

allow peerPE decides which VPNv4 routes to import into a specific VRF

allow peerPE decides which VPNv4 routes to not import into a specific VRF

allow peerCE decides which VPNv4 routes to import into a specific VRF

allow peerCE decides which VPNv4 routes to not import into a specific VRF

AS PATH

NED

Oorigin

Local -Preference

LSA5

LSA2

LSA1

LSA3

The circuit-level of the s4/0/0 interface is Leve1-1

The Cost value of the s4/0/0 interface is 20

The s4/0/0 interface sends an IIH cycle of 30S

The s4/0/0 interface supports IPv6

Increase the amount of available VLANs

Reduce the waste of IP addresses

Increase the flexibility of addressing

Implement the isolation of broadcast domains between Sub-VLANs

True

false

due to MThe CE device is already bound to the VPN, so there is no need to bind the VPN to the PE connected to the MCE device.

MCEThe device can determine the source of the routing information according to the interface that receives the routing information, and maintain it in the routing forwarding table of the corresponding VP.

The implementation principle of MCE is to create its own routing and forwarding table for different VPNs on the MCE device and bind it to the corresponding interface.

configureMCE,A CE can be connected to multiple VPNs at the same time, which not only realizes complete isolation of services between different VPN users, but also reduces the investment cost of network equipment.

In the routing table, use "OSPThe routing table entry identified by the F" identifier can only be learned through Type 3 LSAs

In the routing table, use "OSPThe routing table entry identified by the F" identifier can only pass through Type 1 LSAs

In the routing table, useThe routing table entry identified by the "OSPF" identifier can be learned through the 1/2/3/5 type LSA

In the routing table, use"O_ The routing table entry identified by the ASE" identifier can only be learned through route import.

The data area of the Router-LSA contains the Link-Local address

The data area of the Router-LSA contains the interface of the local neighbor ID

Similar to OSPFv2, the Option field exists in the LSA header instead ofRouter-LSA data area

When L in the header of LSAS When type=0x0001, the data area representing LSA isRouter-LSA

Both routers are Level-1type.

Both routers remain the default type.

One of the two routers can be a Level-1-2 type, and the other can be a Leve1-1 type.

ISIS with two routersProcess IDs must be the same.

DSCP set to decimal 36

IP ToS is set to 0xEF

IP Experimental EEN

DSCP set to decimal 5

bitstream 101110

MPLS system has many kinds of label publishing protocols, such as LDP is a kind of label publishing protocol

MPLS supports single-layer labels and multi-layer labels

the label is a fixed-length identifier with only local significance, used to uniquely identify the FEC to which a packet belongs

the label is carried by the header of the MPLS packet, and has global significance, that is, the label value of all routers cannot be repeated

Advertising Router is set as the router of ASBR ID

NetMask is set to all 0s

Link State ID is set to the destination network segment address

Use Link State ID and Advertising A router can uniquely identify an LSA

NSRAfter this is enabled, if the main control board fails before the batch backup of services is completed, the NSR switchover cannot be completed.

NSR standby routers need to negotiate the ability to support NSR through specific packets

turn onNSFAfter that, the router is switched between active and standby, and the routing table and forwarding table remain unchanged, so the traffic will not be lost during the GR time.

NSF routers do not need to negotiate the ability to support NSF through specific packets

interface GigabitEthernet0/0/1 undo eth-trunk 1

interface GigabitEthernet0/0/1 undo shutdownwn

Member interfaces can be added to a link aggregation group enabled by the following command: interface GigabitEthermet0/0/1 shutdownwn

interface GigabitEthernet0/0/1 trunkport GigabitEthernet0/0/1 interface GigabitEthermet0/0/1 undo shutdownwn

Route-policy

ACL

IP-prefx

AS-path-filter

[0, less-equal-value]

[mask-length, less- equal-value]

[less equal-value, 32]

no limit

Type1

Type2

Type3

Type4

Type5

The firewall's own security zone can be deleted

The same interface of the firewall can belong to different security zones

Different security zones of the firewall can have the same priority

Different interfaces of the waterproof wall can belong to the same security area

device the state between R3 is "2-way". So what can you conclude from this output?

Router R2 is not a DR

Router R3 is not a DR, nor a BDR

router there is no full adjacency between R2 and router R3

routerR4 is DR

Router R2 is DR or BDR

Community

AS Path

Originator ID

MED

host IP address

Host MAC address

Layer 3 VNI

Layer 2 VNI

The two routers are configured for area authentication and interface authentication respectively, and the passwords are the same, then the two routers can establish a neighbor relationship

After configuring area authentication, the IIH, SMP, and LSP sent by the router must carry the authentication TLV.

After configuring interface authentication, the IIH sent by the router must carry the authentication TLV

Interface authentication can authenticate the Hello packets of Leve1-1 and Leve1-2

Gigabitethernet1/0/1 and Gigabitethernet1/0/2 can join the same aggregation group without changing the current configuration

After link aggregation is configured on both SWA and SWB, if the switches SWA and SWB enable MSTP, then the interface status of Gigabitethernet1/0/1 and Gigabitethernet1/0/2 in MSTP is the same

Because of different link types, Gigabitethernet1/0/1 and Gigabitethernet1/0/2 cannot join the same aggregation group

Only by changing the configuration of Gigabitethernet1/0/2 to be consistent with Gigabitethernet1/0/1, the two can join the same aggregation group

TRUE

FALSE

After the network converges, R1 is DR

After the network converges, a new broadcast link is set to R4, and the priority of R4 is 150. When the network converges again, R4 is DR

After the network converges, R1 is powered off and restarted, and when the network converges again, R3 is the DR

After the network converges, the engineer modifies the priority of R1 to 100, the priority of R2 to 10, and the default value of R3. When the network is closed again, R1 is DR, R2 is BDR

239.0.0.0-239.255 255 255

241.0.0.0-241.255.255.255

twenty two4 .0.0.0-224 255 255 255

240.0.0.0-254 .255 255.255

226.0.0.0-226 .255 255.255

In the case of CE multi-homing, enabling the BGP AS number replacement function may cause routing loops. BGP So can be used to prevent routing loops in VPN sites.

When BGP is used to exchange routing information between PE and CE, if the autonomous systems where the two VPN sites are located use the same private AS number, the AS number replacement function can be used to replace the received AS number with any specified AS number. The As number in the private network route, to prevent the route from being discarded due to repeated AS numbers

When BGP is used to exchange routing information between PE and CE, there is no need to import private network routes into BGP on PE.

In the Hub & Spoke scenario, when Hub-CE and Hub-PE use IGP, Spoke-PE and Spoke-CE cannot use EBGP

not-advertise is the default parameter of the abr-summary command, that is, if the abr-summary command does not specify advertise, the default is not-advertise

advertise is the default parameter of the abr-summary command, that is, if not-advertise is specified in the abr-summary command, the default is advertise

The abr-summary command is a command in the OSPF area view.

The asbr-summary command is a command in the OSPF view.

::1/128

FE80::/10

C00::/7

2000::/3

300 4200

1234 1400

3100

100

Perform source IP address and source port conversion at the same time

Only perform source IP address translation

Only perform destination IP address translation

Convert destination IP address and destination port

It includes both the link-local address of this interface and all the addresses in the same area on this router.TPv6 prefix.

Contains the link-local address of this interface, and also includes all IPv6 on this interfaceprefix.

The option field exists in the header of the LSA, not the Link LSAdata area

like Link-LSA one of Prefix of Prefix Options Field is 0x00, then the Prefix Not included in IPv6 unicast calculations.

CHAPThe user name must be configured on the interface of the authenticated party for authentication

If the authenticator does not have a user name configured, the password may not be configured on the interface of the authenticated party.

Pass M using authentication sequence ID, nonce and keyD5 algorithm calculates a Hash value

Three packet exchanges are required for authentication, and only the user name is transmitted on the network without the password.

This router does not have an OSPF process ID configured

The area ID configured by this router and the area I of its neighbor routersD is different

This router is not configured with the authentication function, but the neighbor router is configured with the authentication function

This router's advertised network address does not match the interface mask

Host ARP Advertisement

BUM packet forwarding

hostMAC address advertisement

Host IP route advertisement

ebgp max hop

BGP certification

BGP route filtering

BGP GSTM

TRUE

FALSE

The prefix is learned through other IBGP neighbors, or the prefix is learned from EBGP neighbors, or the prefix is learned through route importarrived

Prefixes that exist in the routing table

The prefix is learned through other BGP neighbors, or the prefix is locally through network or route introduction learned

The prefix is learned via EBGP neighbors, or the prefix is locally via network or route introduction learned

The prefix is learned from EBGP neighbors, or the prefix is learned from RR

5Class LSA

7Class LSA

1Class LSA

4Class LSA

Class 2 LSA

[Huawei]interface GigabitEthernet 0/0/1 [Huawei-GigabitEthernet0/0/1]port link type trunk

[Huawei-GigabitEthernet0/0/1port trunk allow pass vlan 10

[Huaweijinterface GigabitEthernet 0/0/1

[Huawei-GigabitEthernet0/0/1]port link type access [Huawei GigabitEthernet0/0/1]ipsg enable

. [Huawei]interface GigabitEthernet 0/0/1

[Huawei-GigabitEthernet0/0l]port link-type access [Huawei-GigabitEthernet0/0/1 ]port-security enable

[Huawei]interface GigabitEthernet 0/0/1

[Huawei-GigabitEthernet0/0/1 ]port link type access [Huawei-GigabitEthernet0/0/1]port isolate enable

R3 andR1 Systemm ID Repeat

R3 and R1 have different area numbers

R3 andR1 IS-Leve1 Do not match

R3 andR1 IIH Authentication failed

True

false

existIn the hello packet sent by the OSPF neighbor in the NSSA area, in the option field ofN position 0, E position 1

NSSAA default LSA will be automatically generated in the area to access the external network

The NSSA area will generate seven types of L SAs to advertise external routes. The FA addresses in the seven types of L SAs are used to prevent loops.

existIn the hello packet sent by the OSPF neighbor in the NSSA area, the position of the option field is 1, and the position of E is 0.

filter-policy

route-policy

ip extcommunity- filterr

traffic-policy

Use the loopback interface to establish an EBGP neighbor relationship and configure EBGP Multi-hop, configure the loopback interface as the update source, and then use IGP to achieve equal-cost path load sharing between loopback addresses)

To configure the EBGP neighbor relationship with the loopback interface as the update source, the IGP in each AS needs to introduce two equal-cost paths to the EBGP neighbor loopback interface address; and you need to use the command "next-hop-local"

Use the command "ebgp-load on both ends"-balance"

To configure the EBGP neighbor relationship with the loopback interface as the update source, the IGP in each AS needs to introduce two equal-cost paths to the EBGP neighbor loopback interface address; and you need to use the command"ebgp-maxhop" and "next-hop-local"

If this command is not configured, the device will import the external routing protocol to IS-I by default.

The routes are all external release

It will restrict the routing entries generated by the device itself from publishing to the outside world.

This command will filter the link status information published externally.

There is no unicast route from RTB to RTA, which causes RTB to fail the RPF check of the source.

The multicast network dynamically elects RP, and RTA fails to check the RPF of BSR.

The RP elected by RTA is not RTB

The RP is statically configured on the multicast network, while the RTA router is not statically configured with the RP

Modify the next hop of traffic originating locally

In the scenario where the enterprise network has multiple ISP exits, different network segments of the intranet access the Internet through different ISP exits.

On the core switch, the mutual access traffic between the intranet and the extranet is pulled to the side-mounted security detection device

On the core switch, the traffic accessing each other between the internal network and the external network is pulled to the AC device connected by the side.

All VLANs share one spanning tree instance

Multiple bridges share a spanning tree instance

eachVLAN owns a spanning tree instance

multipleVLANs share a spanning tree instance

True

false

Insufficient link bandwidth

Subnet mask mismatch

Inconsistent link layer protocols at both ends

The IP addresses of both ends are not on the same network segment