Pass the Cisco CCNP Service Provider 300-540 Questions and answers with ExamsMirror

Comprehensive and Detailed Explanation (Cisco NFVI / Virtualization Knowledge)

SR-IOV (Single Root I/O Virtualization)allows a VM to access the network interface hardwaredirectly, without going through the hypervisor’s virtual switch.

This is achieved by:

Assigning Virtual Functions (VFs) directly to VMs

Allowing high-performance, low-latency packet I/O

Bypassing the hypervisor datapath

Therefore, SR-IOV doesnotbypass the guest OS; it bypasses thehypervisor I/O virtualization layer, delivering near-native performance.

Thus the correct answer isC.

In Cisco NFVI, themanagement noderelies heavily on Docker containers for:

NFVIS management functions

VIM services

Orchestration components

If the management node fails to start and the system shows:

docker.service: inactive (dead)

…then all Docker-based platform services also fail to start.

The correct recovery action is torestart the Docker engine:

systemctl restart docker

This brings up:

All NFVI-required Docker containers

Management services

REST APIs and cluster components

Why other answers are incorrect:

docker-kibana→ Only affects Kibana logging container

docker-cobbler→ Used for provisioning, not core NFVI management

kube-apiserver→ Part of Kubernetes cluster, but relies on Docker; restarting it won’t help until Docker is running

Thus, the correct answer isB. docker.

Comprehensive and Detailed Explanation

BGP Flowspec allows routers to distributetraffic-filtering rulesusing BGP NLRI.

To enable Flowspec, after neighbors are configured, the essential next step is:

✔Activate the Flowspec address-family under BGP

Example:

router bgp 65000

address-family ipv4 flowspec

neighbor X.X.X.X activate

exit-address-family

This enables:

FlowSpec NLRI exchange

Distribution of drop rules (rate-limit, redirect, null route, etc.)

Automatic ACL/class-map/policy-map generation on edge routers

Why the other options are incorrect:

B. Set BGP routing process→ already done when neighbors were configured

C. Activate neighbors→ only makes senseinsidean address-family; flowspec AF must be enabled first

D. Configure route reflector→ optional and not required for Flowspec to operate

Thus, the correct next step isA. Configure Flowspec for the BGP address-family.

Cisco Umbrella DNS-layer security:

Blocks malicious domains used inphishing,malware,C2 communications, andransomware

Stops threatsbeforeconnections are made

Uses DNS-based filtering and threat intelligence

It doesnotmitigate:

DDoS (needs scrubbing centers)

Brute force login attempts

Zero-day exploits directly

Thus,Ais correct.

In a VXLAN BGP EVPN fabric, each VTEP (NVE interface) must useBGP EVPN as the host-reachability protocolso that MAC/IP information and VTEP reachability are exchanged through the control plane.

From the exhibit:

LEAF-SW-1 – interface nve1

source-interface loopback0

No host-reachability protocol bgp

Host Learning Mode: Data-Plane in show nve interface

LEAF-SW-2 – interface nve1

source-interface loopback0

host-reachability protocol bgp configured

This mismatch causes one VTEP to rely ondata-plane flood-and-learn, while the other usesEVPN BGP control-plane learning, leading to inconsistent and “corrupted” MAC/IP and ARP/ND information between the leaf switches.

The fix is to configure LEAF-SW-1 to also use BGP for host reachability:

interface nve1

host-reachability protocol bgp

Options B and D are incorrect because anycast VTEP designs intentionally share the sameprimaryloopback IP while usingdifferent secondary IPsandunique BGP router IDs. Option A (removing suppress-arp) does not correct the control-plane mismatch.

Therefore, enabling host-reachability protocol bgp on LEAF-SW-1 (OptionC) resolves the issue.

For a site-to-site IPsec VPN, each peer must configure apre-shared keytied to thepublic IP address of the remote VPN peer:

crypto isakmp key address

From the diagram:

R1 outside IP:192.168.10.1/24

R2 outside IP:192.168.20.2/24← remote peer for R1

In the current R1 configuration, the ISAKMP key is incorrectly bound to192.168.10.2, which is a local next-hop/ISP address on R1’s own subnet, not the R2 public IP. Because the pre-shared-key address does not match the source IP of R2’s IKE packets, phase 1 negotiation fails and the tunnel never comes up.

The correct configuration on R1 must therefore be:

crypto isakmp key vpnuser address 192.168.20.2

Options A and C incorrectly change the default route (next hop must be the local ISP router, not R2’s public IP or a LAN address). Option D uses an internal address (10.1.1.2), which is not the IP used for IKE on the Internet.

Comprehensive and Detailed Explanation

SNMP traps in Cisco NFVIS (and in SNMP generally):

Areunsolicited notifications

Sent from the NFVIS deviceto the SNMP manager

Indicate alarms, changes, or significant operational events

Donotrequire polling

Examples:

Disk failures

VM crashes

Host status changes

Resource alarms

Why the others are wrong:

Adescribes SNMP monitoring (done by the manager with GET requests)

BSNMP cannotcontrolhost activities

DSNMP GET retrieves a variable, but traps sendunsolicitednotifications

Thus, the correct answer isC.

In Cisco data center and cloud-scale designs, adouble-sided vPC(also called vPC-to-vPC) is used when both ends of a Layer 2 port channel are formed by a pair of switches that operate as vPC peers. In this model:

On the aggregation or leaf side, two switches (in this case,LEAF1 and LEAF2) form a vPC domain with a vPC peer-link and keepalive.

On the access or ToR side, two switches (in this case,TOR1 and TOR2) must also form their ownvPC domainwith a peer-link and vPC keepalive.

The port-channel that interconnects the two vPC domains is then configured as a vPC on both sides, creating a vPC-to-vPC topology.

The problem statement specifies thatLEAF1 and LEAF2 are already configured as vPC peers. For a double-sided vPC to work, the other side (TOR1 and TOR2) must also behave as a single logical entity for the downstream Cisco UCS server and for the upstream vPC connection towards LEAF1 and LEAF2. This is only achieved when TOR1 and TOR2 are configured as vPC peers with:

A vPC domain ID

A vPC peer-link between TOR1 and TOR2

vPC member port-channels towards LEAF1 and LEAF2 and towards the Cisco UCS server

Therefore, the next required step is to configure avPC between TOR1 and TOR2.

Evaluation of the options:

Option A, “Add all the switches to the fabric,” is generic and not specific to vPC configuration. It does not address the technical requirement to form a vPC domain on the ToR side.

Option B, “Configure peering between LEAF1 and LEAF2 and TOR1 and TOR2,” is incorrect because vPC peering is only configured between the two switches that form each vPC domain (LEAF1–LEAF2 and TOR1–TOR2), not across all four switches together.

Option C, “Configure MSTP between TOR1 and TOR2,” is not required for establishing a double-sided vPC. vPC designs rely on the vPC control plane and the peer-link, not on spanning-tree between the vPC peers for normal operation.

Option D, “Configure a vPC between TOR1 and TOR2,” correctly describes configuring TOR1 and TOR2 as a vPC pair (vPC domain with peer-link), which is the mandatory step to create a double-sided vPC topology with LEAF1 and LEAF2.