CCNP Network Function Virtualization Practice Test 2 — 15 Questions

Question 1

A company is deploying a virtualized router (CSR1000v) on VMware vSphere. The VNF must support high throughput and low latency. Which vSphere configuration option should the architect select to optimize network performance?

Accepted Answer

Enable SR-IOV on the physical NIC and assign virtual functions to the VM.. SR-IOV (Single Root I/O Virtualization) allows a physical NIC to present multiple virtual functions (VFs) directly to a VM, bypassing the hypervisor's virtual switch. This reduces latency and CPU overhead, making it ideal for high-throughput, low-latency VNFs like the CSR1000v. Option B is correct because SR-IOV provides near-native performance by allowing the VM to directly access the NIC hardware.

Answer

Use the default e1000 NIC driver.

Answer

Use VMXNET3 paravirtualized NIC.

Answer

Configure the VM with multiple vCPUs and large memory.

Question 2

An architect is designing an SD-WAN policy to ensure that real-time video traffic from headquarters to branch offices is always sent over the most reliable transport, while all other traffic uses the least-cost path. Which type of policy should be used to achieve this?

Accepted Answer

Centralized data policy configured on vSmart.. A centralized data policy configured on vSmart is correct because it allows the SD-WAN controller to enforce application-aware routing decisions across the fabric. By matching real-time video traffic and steering it over the transport with the highest loss/reachability metrics (most reliable), while using a separate rule to direct all other traffic over the least-cost path, the policy is applied globally from the vSmart controller without requiring per-router configuration.

Answer

Localized data policy applied on the vEdge router.

Answer

Centralized control policy for route manipulation.

Answer

Localized app-route policy on the branch vEdge.

Question 3

A network team must design a QoS policy for a WAN link that carries voice, video, and data. The policy must ensure that voice traffic is never dropped, even during congestion. Which queuing mechanism should be used for the voice class?

Accepted Answer

Low-latency queuing (LLQ).. Low-latency queuing (LLQ) is the correct choice because it combines strict priority queuing with CBWFQ, allowing voice traffic to be placed in a strict priority queue that is serviced first before any other queues. This ensures that voice packets are never dropped due to congestion, as long as the configured policer rate is not exceeded, meeting the requirement that voice traffic is never dropped.

Answer

Class-based weighted fair queuing (CBWFQ).

Answer

Weighted random early detection (WRED).

Answer

First-in, first-out (FIFO) queuing.

Question 4

Examine the following configuration snippet:

interface GigabitEthernet0/1
 ip address 192.168.1.1 255.255.255.0
 ip ospf hello-interval 20
 ip ospf dead-interval 80

What is the effect of this configuration?

Accepted Answer

The OSPF hello interval is changed to 20 seconds, and the dead interval is changed to 80 seconds, maintaining the default 4:1 ratio.. Option A is correct because the configuration explicitly sets the OSPF hello interval to 20 seconds and the dead interval to 80 seconds, which maintains the default 4:1 ratio (dead = hello × 4). OSPF allows manual configuration of these timers, and as long as both sides of the adjacency match, the ratio can be any value; the 4:1 default is not enforced by the protocol.

Answer

The OSPF hello interval is changed to 20 seconds, but the dead interval remains at the default of 40 seconds.

Answer

The OSPF hello interval is changed to 20 seconds, and the dead interval is automatically set to 60 seconds.

Answer

This configuration will cause OSPF adjacency failure because the dead interval must be exactly 4 times the hello interval.

Question 5

Consider the following configuration:

router eigrp TEST
 network 10.0.0.0 0.255.255.255
 metric weights 0 1 0 1 0 0

What is the effect of the 'metric weights' command?

Accepted Answer

It changes the EIGRP metric calculation to use only bandwidth and delay, which is the default behavior.. The 'metric weights' command in EIGRP allows you to modify the K values used in the composite metric formula. The default K values are K1=1, K2=0, K3=1, K4=0, K5=0, which means only bandwidth (K1) and delay (K3) are used. The command 'metric weights 0 1 0 1 0 0' explicitly sets K1=1, K3=1, and all others to 0, which matches the default behavior and does not change the metric calculation.

Answer

It changes the EIGRP metric calculation to use bandwidth, delay, and reliability.

Answer

It changes the EIGRP metric calculation to use only delay.

Answer

It disables the EIGRP metric calculation, causing all routes to have the same metric.

Question 6

Given the following configuration:

interface GigabitEthernet0/0
 ip address 10.1.1.1 255.255.255.0
 ip pim sparse-mode
 ip igmp version 3

What is the purpose of the 'ip igmp version 3' command?

Accepted Answer

It enables IGMP version 3, which allows hosts to join multicast groups from specific sources, supporting SSM.. The 'ip igmp version 3' command enables IGMPv3 on the interface, which supports Source-Specific Multicast (SSM) by allowing hosts to specify both the multicast group and the source address in their membership reports. This is essential for SSM operation with PIM sparse-mode, as IGMPv3 provides the source filtering capability that IGMPv2 lacks.

Answer

It enables IGMP version 3, which increases the number of multicast groups supported to 1024.

Answer

It enables IGMP version 3, which is required for PIM dense-mode operation.

Answer

It enables IGMP version 3, which disables IGMP snooping on the interface.

Question 7

Examine this configuration:

interface GigabitEthernet0/0
 ip address 192.168.1.1 255.255.255.0
 ipv6 address 2001:db8::1/64
 ipv6 ospf 1 area 0

What is the effect of the 'ipv6 ospf 1 area 0' command?

Accepted Answer

It enables OSPFv3 process 1 on this interface and assigns it to area 0.. The 'ipv6 ospf 1 area 0' command enables OSPFv3 (the IPv6 version of OSPF) on the specified interface, assigns it to OSPFv3 process 1, and places the interface in area 0 (the backbone area). This is the correct syntax for activating OSPFv3 on an interface under a specific process and area, independent of any global OSPFv3 process configuration.

Answer

It enables OSPFv2 process 1 on this interface and assigns it to area 0.

Answer

It enables OSPFv3 on this interface but the process ID must match the router ospf process ID; if not, it will be ignored.

Answer

It enables OSPFv3 on this interface but area 0 is invalid for IPv6; OSPFv3 uses area 0.0.0.0.

Question 8

Consider the following BGP configuration:

router bgp 65000
 bgp router-id 1.1.1.1
 neighbor 10.1.1.2 remote-as 65001
 neighbor 10.1.1.2 route-map SET_MED out
!
route-map SET_MED permit 10
 set metric 50

What is the effect of this configuration?

Accepted Answer

Routes advertised to 10.1.1.2 will have the MED set to 50, influencing inbound path selection in AS 65001.. The route-map SET_MED is applied to outbound updates to neighbor 10.1.1.2, setting the MED (Multi-Exit Discriminator) attribute to 50. MED is a metric that influences inbound path selection in the neighboring AS (AS 65001), telling its routers which path to prefer when multiple entry points exist into AS 65000. Therefore, option A correctly describes the effect.

Answer

Routes advertised to 10.1.1.2 will have the MED set to 50, influencing outbound path selection from AS 65000.

Answer

Routes received from 10.1.1.2 will have the MED set to 50.

Answer

The MED value will be set to 50 for all routes in the BGP table.

Question 9

Given the following configuration:

interface GigabitEthernet0/0
 ip address 10.0.0.1 255.255.255.0
 ip access-group 101 in
!
access-list 101 permit tcp 192.168.1.0 0.0.0.255 any eq 80
access-list 101 deny ip any any

What is the effect of this configuration?

Accepted Answer

Incoming traffic from 192.168.1.0/24 to any destination on port 80 is permitted; all other incoming traffic is denied.. The configuration applies access-list 101 inbound on GigabitEthernet0/0. The first ACE permits TCP traffic from source network 192.168.1.0/24 to any destination on port 80 (HTTP). The second ACE denies all other IP traffic. Since the access list is applied in the inbound direction, it filters traffic entering the router through that interface. Therefore, only incoming traffic matching the permit statement is allowed; everything else is denied.

Answer

Outgoing traffic from the router to 192.168.1.0/24 on port 80 is permitted; all other outgoing traffic is denied.

Answer

Incoming traffic from any source to 192.168.1.0/24 on port 80 is permitted; all other incoming traffic is denied.

Answer

The access-list will permit all TCP traffic from 192.168.1.0/24, regardless of destination port.

Question 10

What is the default OSPF hello interval on an Ethernet link?

Accepted Answer

10 seconds. On Ethernet (broadcast multi-access) links, OSPF defaults to a hello interval of 10 seconds, as specified in RFC 2328. This interval allows OSPF routers to quickly detect neighbor failures while keeping control overhead low. The dead interval is automatically set to 40 seconds (four times the hello interval) on such links.

Answer

30 seconds

Answer

40 seconds

Answer

5 seconds

Question 11

Which BGP attribute is preferred with the lowest value?

Accepted Answer

MED. MED (Multi-Exit Discriminator) is a BGP attribute that is preferred with the lowest value. It is used to influence inbound traffic to an AS when multiple entry points exist, and a lower MED value is more preferred over a higher one.

Answer

Local Preference

Answer

Weight

Answer

Origin

Question 12

What is the maximum hop count for EIGRP?

Accepted Answer

100. EIGRP uses a maximum hop count of 100 by default to prevent routing loops. This is a hard limit; if a route's hop count exceeds 100, EIGRP considers it unreachable. This value is configurable via the 'metric maximum-hops' command under the EIGRP process.

Answer

15

Answer

255

Answer

16

Question 13

Drag and drop the steps of VNF life cycle management into the correct order, from first to last.

Accepted Answer

Onboard VNF package into NFVI. The correct order follows the ETSI NFV lifecycle: first onboard the VNF package, then instantiate the VNF, configure the VNF, scale the VNF as needed, and finally terminate the VNF when no longer required.

Question 14

Drag and drop the steps of VNF service chain instantiation into the correct order, from first to last.

Accepted Answer

Define service chain requirements. Service chain instantiation begins with defining the chain, then selecting VNFs, allocating resources, connecting VNFs via virtual links, and finally testing the chain to verify functionality.

Question 15

Drag and drop the steps of deploying a virtual router as a VNF into the correct order, from first to last.

Accepted Answer

Upload virtual router image to hypervisor. Deploying a virtual router VNF starts with uploading the image, then creating the VM, attaching virtual interfaces, configuring routing protocols, and finally verifying connectivity.