Question 1

Which three steps are required to configure QPPB on Cisco IOS XR routers? (Choose three.)
A) Apply a QPPB route policy to the BGP process using the table-policy command
B) Apply a QPPB route policy to the BGP neighbor using the route-policy command
C) Define a QPPB route policy to match the customer routes, then set the IP precedence or qos-group
D) Define a QPPB route policy to match the customer IP precedence or qos-group markings, then set the BGP community
E) Enable QPPB on an interface using the ipv4 bgp policy propagation input ip-precedence|qos-group destination|source command
F) Enable QPPB on an interface using the ipv4 bgp policy propagation output ip-precedence|qos-group destination|source command

Accepted Answer

A. Apply a QPPB route policy to the BGP process using the table-policy commandC. Define a QPPB route policy to match the customer routes, then set the IP precedence or qos-groupE. Enable QPPB on an interface using the ipv4 bgp policy propagation input ip-precedence|qos-group destination|source command

Question 2

Referring to the Cisco IOS XR configuration exhibit,  which labels will be advertised by the router with this configuration?
A) Only the label for 10.1.1.1/32 will be advertised to all the LDP peers.
B) Labels for all prefixes will be advertised to the 10.1.1.1 LDP peer.
C) Labels for all prefixes will be advertised to all the LDP peers.
D) No labels will be advertised to any LDP peers.

Accepted Answer

A

Question 3

Which of the following three statements are correct regarding IPv6 QoS?  (Choose three.)
A) The traffic class field in the IPv6 header can be used to set specific precedence or DSCP values.
B) A 20-bit flow label field enables per-flow processing.
C) DS-TE is not supported by IPv6.
D) Per-hop behavior in IPv6 networks is based on EXP bits.
E) IPv6 QoS features are configured using the modular QoS CLI on Cisco routers.

Accepted Answer

The traffic class field in the IPv6 header is used for QoS marking similar to DSCP. The flow label field allows for per-flow processing, which can be used for QoS. IPv6 QoS features can be configured using the modular QoS CLI on Cisco routers.

Question 4

On the Cisco IOS XR, when using the match protocol command within a class-map to classify traffic, you noticed that the match protocol option on the Cisco IOS XR shows much fewer protocol options than on the Cisco IOS or IOS XE, like there is no option such as the match protocol yahoo-messenger command on the Cisco IOS XR. Why is this?
A) because the Cisco IOS XR router does not have the correct software packages installed
B) because when defining the class-map, the class-map type should be set to type inspect: class-map type inspect class-map-name command
C) because NBAR is not supported on the Cisco IOS XR
D) because flexible packet matching has not been enabled on the Cisco IOS XR router

Accepted Answer

NBAR (Network-Based Application Recognition) is not supported on the Cisco IOS XR, which is why there are fewer protocol options available for traffic classification compared to Cisco IOS or IOS XE.

Question 5

Refer to the Cisco IOS XR policy-map configuration exhibit.  What is wrong with the policy-map configuration?
A) missing the priority percent command under class one and class two
B) missing the police command under class one and class two
C) missing the police command under class three
D) missing the priority bandwidth command under class one and class two
E) missing the bandwidth command under class one and class two

Accepted Answer

The answer of Refer to the Cisco IOS XR policy-map...

Question 6

Which Cisco IOS XR command should be used in order to enable LDP-IGP synchronization for the ISIS IGP protocol?
A) RP/0/RSP0/CPU0:R1(config-isis-if-af)#mpls ldp sync
B) RP/0/RSP0/CPU0:R1(config-isis)#mpls ldp sync
C) RP/0/RSP0/CPU0:R1(config-ldp)#isis ldp sync
D) LDP-IGP synchronization is not supported for the ISIS IGP protocol on Cisco IOS XR platforms

Accepted Answer

The command "mpls ldp sync" is used under the ISIS interface address-family configuration mode to enable LDP-IGP synchronization for ISIS on Cisco IOS XR.

Question 7

When configuring LLQ (strict priority queue) on a traffic class using the Cisco IOS XR priority command on a Cisco ASR9K router, which additional QoS command is required for this traffic class?
A) shape
B) police
C) random-detect
D) bandwidth

Accepted Answer

The "police" command is required to limit the bandwidth of the strict priority queue to prevent it from starving other queues.

Question 8

Only based on the Cisco IOS XR policy-map configuration exhibit,  which statement is correct?
A) All DSCP AF41 marked packets will be dropped when the average queue length reaches 12,000 packets.
B) DSCP AF11 marked packets will be randomly dropped when the average queue length reaches 10,000 packets.
C) DSCP AF11 and AF41 marked packets are guaranteed a minimum bandwidth of 1 Mb/s.
D) DSCP AF11 and AF41 marked packets are guaranteed a maximum bandwidth of 1 Mb/s.

Accepted Answer

The answer of Only based on the Cisco IOS XR...

Question 9

Referring to the Cisco IOS XR show command output exhibit,  what are three possible reasons that the GigabitEthernet0/1/0/10 LDP IGP sync status is not ready? (Choose three.)
A) GigabitEthernet0/1/0/10 is not configured to run LDP.
B) Graceful restart is not configured on the peer.
C) The LDP neighbor on GigabitEthernet0/1/0/10 is not up.
D) The OSPF neighbor on GigabitEthernet0/1/0/10 is not up.
E) LDP is up on GigabitEthernet0/1/0/10, but no label bindings have been received from the peer.
F) GigabitEthernet0/1/0/10 is a member link of Bundle-Ether9000.

Accepted Answer

The answer of Referring to the Cisco IOS XR show...

Question 10

Which item is not available to be used for QoS classification in Cisco IOS XR?
A) MAC SA
B) protocol
C) inner EXP
D) discard-class
E) QoS-group
F) VLAN

Accepted Answer

The answer of Which item is not available to be...

Question 11

On the Cisco IOS XR, which MQC configuration is different than on the Cisco IOS and IOS XE?
A) On the Cisco IOS XR, WRED can only be applied in the output direction.
B) On the Cisco IOS XR, marking can only be applied in the input direction.
C) On the Cisco IOS XR, LLQ can be applied in the input or output direction.
D) On the Cisco IOS XR, LLQ can use up to four priority queues: level 1, level 2, level 3, and level 4.

Accepted Answer

LLQ can be applied in the input or output direction on the Cisco IOS XR, unlike on the Cisco IOS and IOS XE, where it can only be applied in the input direction.

Question 12

When implementing MPLS DS-TE on Cisco IOS XR routers, all aggregate Cisco MPLS TE traffic is mapped to which class type by default?
A) class-type 0 (bandwidth global pool)
B) class-type 1 (bandwidth subpool)
C) class-type 2 (bandwidth priority)
D) class type class-default (bandwidth best-effort)

Accepted Answer

By default, all aggregate Cisco MPLS TE traffic is mapped to class-type 0, which corresponds to the bandwidth global pool in MPLS DS-TE on Cisco IOS XR routers.

Question 13

When implementing MPLS TE tunnels on Cisco IOS XR routers, what is the tunnel setup and hold priority value range, and which value has the highest priority?
A) 0-63, where 0 is the highest priority
B) 0-63, where 63 is the highest priority
C) 0-7, where 0 is the highest priority
D) 0-7, where 7 is the highest priority

Accepted Answer

The tunnel setup and hold priority range for MPLS TE on Cisco IOS XR is 0-7, where 0 is the highest priority.

Question 14

In which two Cisco IOS XR configuration modes can mpls ldp igp sync be configured?  (Choose two.)
A) config-ldp
B) config-if
C) config-ospf-ar
D) config-ospf
E) config-isis

Accepted Answer

The answer of In which two Cisco IOS XR configuration...

Question 15

The Cisco IOS and IOS XE qos pre-classify command allows which kind of packet classification on IP packets that are encapsulated with GRE and IPsec?
A) allows for packets to be classified based on the ToS byte values before packet encryption
B) allows for packets to be classified based on the ToS byte values after packet encryption
C) allows for packets to be classified based on the packet payload before packet encryption
D) allows for packets to be classified based on the packet payload after packet encryption
E) allows for packets to be classified based on the packet header parameters other than the ToS byte values after packet encryption

Accepted Answer

The Cisco IOS and IOS XE qos pre-classify command allows for packets to be classified based on the ToS byte values before packet encryption.

Question 16

When configuring class-based WRED on Cisco routers, which WRED parameter is not user configurable on a Cisco IOS XR but is user configurable on a Cisco IOS and IOS XE?
A) the ingress or egress direction where the class-based WRED policy will be applied
B) the maximum threshold
C) the minimum threshold
D) the mark probability denominator

Accepted Answer

On Cisco IOS XR, the mark probability denominator is not user configurable, whereas it is configurable on Cisco IOS and IOS XE.

Question 17

On a Cisco IOS XR router, which mechanism protects the router resources by filtering and policing the packets flows that are destined to the router that is based on defined flow-type rates?
A) LLQ
B) LPTS
C) Committed Access Rate
D) Control Plane Policing
E) Management Plane Protection
F) NetFlow
G) ACL

Accepted Answer

LPTS (Local Packet Transport Services) is a mechanism on Cisco IOS XR routers that protects router resources by filtering and policing packet flows destined to the router based on defined flow-type rates.

Question 18

Which Cisco IOS XR high-availability feature is used to prevent routes from being used before LDP converges?
A) LDP session protection
B) LDP-IGP synchronization
C) BFD
D) IGP session protection

Accepted Answer

LDP-IGP synchronization is used to ensure that routes are not used until LDP has converged, preventing blackholing of traffic.

Question 19

When troubleshooting LDP operations on the Cisco IOS and IOS XE routers, what is one of the first things that should be verified?
A) if running OSPF as the IGP, ensure that OSPFv3 has been enabled
B) check if the ip cef command has been enabled
C) verify in the running configurations that all of the required LDP interfaces are defined under the mpls ldp command configuration mode
D) verify if there are any access lists that are denying TCP and UDP port 464 packets

Accepted Answer

LDP (Label Distribution Protocol) relies on Cisco Express Forwarding (CEF) for label switching, so ensuring that CEF is enabled is a fundamental step in troubleshooting LDP operations.

Question 20

Refer to the Cisco IOS XR configuration exhibit.  Which statement is correct?
A) The backup tunnel-te 10 tunnel is using the highest setup and hold priority settings of 7.
B) The backup tunnel path is learned dynamically.
C) The fast-reroute command is missing under the (config-mpls-te-if)# configuration mode.
D) Interface gi0/0/0/10 is the protected link.

Accepted Answer

The answer of Refer to the Cisco IOS XR configuration...

Exam 16: Designing Cisco Data Center Infrastructure (DCID)

Which three steps are required to configure QPPB on Cisco IOS XR routers? (Choose three.)

Referring to the Cisco IOS XR configuration exhibit, which labels will be advertised by the router with this configuration?

Which of the following three statements are correct regarding IPv6 QoS? (Choose three.)

Refer to the Cisco IOS XR policy-map configuration exhibit. What is wrong with the policy-map configuration?

Which Cisco IOS XR command should be used in order to enable LDP-IGP synchronization for the ISIS IGP protocol?

When configuring LLQ (strict priority queue) on a traffic class using the Cisco IOS XR priority command on a Cisco ASR9K router, which additional QoS command is required for this traffic class?

Only based on the Cisco IOS XR policy-map configuration exhibit, which statement is correct?

Referring to the Cisco IOS XR show command output exhibit, what are three possible reasons that the GigabitEthernet0/1/0/10 LDP IGP sync status is not ready? (Choose three.)

Which item is not available to be used for QoS classification in Cisco IOS XR?

On the Cisco IOS XR, which MQC configuration is different than on the Cisco IOS and IOS XE?

When implementing MPLS DS-TE on Cisco IOS XR routers, all aggregate Cisco MPLS TE traffic is mapped to which class type by default?

When implementing MPLS TE tunnels on Cisco IOS XR routers, what is the tunnel setup and hold priority value range, and which value has the highest priority?

In which two Cisco IOS XR configuration modes can mpls ldp igp sync be configured? (Choose two.)

The Cisco IOS and IOS XE qos pre-classify command allows which kind of packet classification on IP packets that are encapsulated with GRE and IPsec?

When configuring class-based WRED on Cisco routers, which WRED parameter is not user configurable on a Cisco IOS XR but is user configurable on a Cisco IOS and IOS XE?

On a Cisco IOS XR router, which mechanism protects the router resources by filtering and policing the packets flows that are destined to the router that is based on defined flow-type rates?

Which Cisco IOS XR high-availability feature is used to prevent routes from being used before LDP converges?

When troubleshooting LDP operations on the Cisco IOS and IOS XE routers, what is one of the first things that should be verified?

Refer to the Cisco IOS XR configuration exhibit. Which statement is correct?