300-540 Cisco Designing and Implementing Cisco Service Provider Cloud Network Infrastructure (SPCNI v1.0) Free Practice Exam Questions (2025 Updated)

In a VXLAN BGP EVPNMulti-Siteenvironment:

DCI trackingmonitors the health of the DCI links. If all DCI-tracking interfaces go down, the leaf can incorrectly keep advertising or learning remote MAC/IP reachability, leading to packet loss and sub-optimal forwarding for servers in that VLAN/L2VNI.

For proper operation, eachDCI-facing interfacemust be enabled with evpn multisite dci-tracking so that the Multi-Site border leaf tracks reachability over that link.

When using EVPN Multi-Site, BUM (broadcast, unknown unicast, multicast) traffic toward remote sites is typically handled viaingress replication, not multicast groups, for each L2VNI participating in Multi-Site. The configuration snippet shows an L2VNI (vn-segment 16535) still mapped to mcast-group 239.1.1.0, which is inconsistent with Multi-Site recommendations and contributes to packet loss.

Therefore, to fix the problem:

Enable DCI tracking on the uplink:

interface Ethernet1/1

evpn multisite dci-tracking

This restores proper DCI-link state monitoring for Multi-Site. →Option C

Change the L2VNI behavior from multicast to Multi-Site ingress replication:

Under the VNI for VLAN 11, configure:

evpn

vni 16535 l2

multisite ingress-replication

or the equivalent command for the specific NX-OS release, thereby aligning the L2VNI with EVPN Multi-Site design and eliminating packet loss. →Option D

Options A and B are ELAM (embedded logic analyzer) filters used only for packet capture and do not resolve the forwarding issue.

Option E is an ACL line unrelated to EVPN VXLAN or DCI tracking and does not address the underlying problem.

Comprehensive and Detailed Explanation From Cisco SP Cloud Network Infrastructure Security Knowledge

Cloud security compliance frameworks (such as ISO 27001, PCI-DSS, GDPR, SOC 2, HIPAA) require:

Evidence of security events

Retention of logs for audit periods

Ability to generate compliance reports

Traceability and accountability

Incident investigation support

Effective log management enables:

Centralized collection of application, network, and system logs

Storage of logs for mandated retention periods

Generation ofaudit-ready reports

Documentation required for compliance assessments

Demonstration that monitoring and security controls are active and functioning

Therefore, the role of log management in regulatory compliance is primarily aboutdocumentation, traceability, auditing, and reporting, which aligns only with Option A.

The other options do not directly serve regulatory compliance requirements:

Brelates to resource optimization, not compliance.

Crefers to interoperability, which is unrelated to regulatory auditing.

Dimproves security but does not directly address compliance documentation.

Comprehensive and Detailed Explanation Based on Designing and Implementing Cisco Service Provider Cloud Network Infrastructure Knowledge

When connectingcarrier-neutral facilities (CNFs)ordata centerswithin the same metropolitan area, service providers typically usehigh-bandwidth, low-latency optical transport methods. The most appropriate and commonly deployed interconnection technology is:

DWDM (Dense Wavelength Division Multiplexing) ring, which provides:

High capacity (10G, 40G, 100G, 400G)

Low latency

Redundancy through ring or mesh topologies

Multi-wavelength multiplexing for cost efficiency

Carrier-grade reliability for metro interconnect services

This aligns with cloud interconnect and metro transport design used in service provider environments.

Evaluation of the Options

A. OSPF backbone area adjacency

This is a routing protocol adjacency, not a physical connection method. It requires a transport link underneath but does not represent the physical interconnect itself.

B. Private wireless connection

Not suitable for CNF or metro DC interconnect because it lacks the bandwidth, reliability, and deterministic performance required for large-scale carrier-grade interconnects.

C. DWDM ring

This is the correct method. DWDM-based metro fiber rings are the standard for connecting carrier-neutral facilities in the same metro region.

D. CAT6e connection

This is limited to short-distance copper Ethernet (tens of meters). It is not used for metro-scale interconnects or between CNFs.

RouterR2is insideAS 100and has three iBGP paths (via R3, R4, R5) toward AS 101. To performiBGP multipathacross these three equal-cost paths, BGP must:

Run the correct BGP process forAS 100

Allow installation of multiple iBGP paths in the routing table

This is done with:

router bgp 100

maximum-paths ibgp 3

router bgp 100– enters the BGP process for AS 100 (correct AS per diagram).

maximum-paths ibgp 3– tells BGP to keep up to 3 iBGP paths to the same destination, enabling CEF to load-share across them.

Other options:

ip load-sharing ibgp 3– not a valid command.

router bgp 101– wrong AS number.

ip load-sharing per-destination– controls CEF hashing but does not enable BGP to install multiple iBGP paths by itself.

Comprehensive and Detailed Explanation

For distancesgreater than 20 miles, valid inter-facility transport options must support:

Metro-scale connectivity

High bandwidth

Low latency

Carrier-grade reliability

Acarrier access Ethernet ring (MEN / Metro Ethernet)is designed for:

Interconnecting data centers or meet-me rooms

Distances far exceeding 20 miles

High-availability layer-2 or layer-3 transport

Why the others are invalid:

CAT6e→ maximum ~100 meters

Multimode fiber→ typically <2 km (~1.25 miles)

Private wireless→ not used for high-capacity DC interconnects, unreliable for core transport

Thus, the only correct carrier-grade method isCarrier access Ethernet ring.

Comprehensive and Detailed Explanation

In Cisco NFVI security architecture, the primary defense againstlateral movement(an attacker moving from one compromised node to another) isnetwork segmentation.

Segmentation:

Separates workloads (compute, storage, management, tenant networks)

Prevents attackers from pivoting inside the NFVI

Reduces blast radius during breaches

Enforces micro-segmented virtual network boundaries

WPA protects Wi-Fi, not NFVI.

WAF protects web apps, not internal movement.

Data encryption protects confidentiality, not lateral movement control.

Thus,network segmentationis the correct solution.

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.

Comprehensive and Detailed Explanation From Exact Extract from my knowledge of Designing and Implementing Cisco Service Provider Cloud Network Infrastructure Outlines without Any External URL or Links:

Container orchestration is the automated management of container lifecycle tasks such as deployment, scaling, failover, and updates. In Cisco cloud and NFV design guidance, typical orchestration platforms includeDocker (with Swarm)andKubernetes, which integrate with Cisco networking and security for cloud-native workloads.

Dockerprovides the container runtime and can also perform basic orchestration through Docker Swarm mode, managing multi-container, multi-host deployments.

Kubernetesis a full-featured orchestration system that automates deployment, scaling, and operations of application containers across clusters. It is the de-facto standard used with Cisco Container Platform and other Cisco cloud solutions.

VMware vCenter, Cisco vManage, and Cisco vSmart focus on virtual machines or SD-WAN control, not container orchestration. Therefore, the correct tools areDocker and Kubernetes (A, D).

Comprehensive and Detailed Explanation From Cisco SP Core Optimization Knowledge

Cisco IOS supportsBGP Multipathfor installing multiple equal-cost BGP routes (both iBGP and eBGP) into the routing table. The correct global BGP command syntax to set the number of allowable parallel BGP paths is:

maximum-paths

For BGP specifically, the form is:

maximum-paths bgp

This enables the router to install up to the specified number of equal-cost BGP routes (iBGP and eBGP) into the RIB and then potentially into the FIB.

Setting:

maximum-paths bgp 6

allowssixparallel ECMP paths learned via BGP—this matches the requirement in the question.

Why the other options are incorrect

B. multipath eibgp 6Not a valid Cisco IOS command.

C. maximum paths bgp routers 6Invalid syntax.

D. maximum-paths eibgp 6The correct keyword isbgp, noteibgp.Cisco does not use “eibgp” in this context; IOS supports BGP multipath across iBGP/eBGP automatically when configured under maximum-paths bgp.

R1 (AS 200) is multihomed to:

SP-1 in AS 300 via neighbor172.16.1.1

SP-2 in AS 400 via neighbor172.16.2.1

R1 must:

Advertiseonly locally originated prefixes(its own network 10.10.0.0/24).

NOTbecome atransit AS—i.e., R1 mustnotadvertise routes learned from one provider to the other.

The configuration includes AS-path access-lists:

ip as-path access-list 1 permit ^$

ip as-path access-list 200 permit ^200

ip as-path access-list 300 permit ^300

ip as-path access-list 400 permit ^400

^$ in AS-path ACL1matcheslocally originated routes(empty AS-path).

ACLs 200, 300, and 400 match routes whose first AS in the path is 200, 300, or 400 respectively (used if we needed to match those provider or customer routes).

To ensure each upstream provider only receiveslocally originatedroutes, we apply AS-path ACL1as anoutbound filter-liston each external BGP neighbor:

router bgp 200

neighbor 172.16.1.1 remote-as 300

neighbor 172.16.1.1 filter-list 1 out ← only advertise local prefixes to SP-1

neighbor 172.16.2.1 remote-as 400

neighbor 172.16.2.1 filter-list 1 out ← only advertise local prefixes to SP-2

This way:

Routes learned from SP-1 (AS 300) willnotbe advertised to SP-2 (AS 400) because their AS-path will begin with 300, not empty, so they fail ACL 1.

Similarly, routes from SP-2 will not be sent to SP-1.

Only R1’s own prefixes are exported, preventing AS 200 from becoming a transit network.

Comprehensive and Detailed Explanation From Cisco SP Security Knowledge

Cisco Always-On Cloud DDoS Protection is a cloud-based, carrier-grade security service used by service providers to protect customers from volumetric and application-layer DDoS attacks.

Its core protection mechanism is the use ofglobal scrubbing centers, which:

Receive diverted attack traffic

Scrub (clean) malicious packets

Forward clean traffic back to the customer

Use behavioral analysis and real-time detection

Protect against volumetric, TCP state-exhaustion, and application-layer attacks

Why other answers are incorrect:

Load balancing (A)doesnotmitigate DDoS attacks; it distributes traffic across servers.

Botnet zombies (B)aresourcesof DDoS attacks, not protection.

Traffic mirroring (C)is used for analysis and monitoring, not active DDoS protection.

Comprehensive and Detailed Explanation From Cisco NFVI + VIM Architecture

Cisco VIM (Virtual Infrastructure Manager) operates as part of Cisco NFVI and requiresspecific mandatory network segmentsto deploy OpenStack-based NFVI environments.

The essential required networks for Cisco VIM include:

✔Provisioning network

Used during bare-metal install of compute and controller nodes

Handles PXE boot, image deployment, and VIM’s management reachability

✔Storage network

Used for Cinder, Swift, Ceph, and Glance back-end storage replication

Ensures predictable latency and bandwidth for NFVI workloads

Other networks exist in VIM (Management, API, Tenant, External), but the question asks for the required foundational segments.

Why the other options are incorrect:

Data plane(B) – used inside NFV workloads but not a required VIM infrastructure network.

Heartbeat(C) – not a defined VIM network segment.

Host network(D) – not a Cisco VIM terminology; provisioning network handles host onboarding.

In a cloud-scale or data center–scale environment,Virtual Extensible LAN (VXLAN)is used as anoverlay technologyto transportLayer 2 segments over a Layer 3 underlay network. VXLAN encapsulates Layer 2 Ethernet frames inside UDP/IP packets, allowing broadcast, unknown unicast, and multicast (BUM) traffic and tenant Layer 2 domains to be extended across a routed IP fabric.

Key points aligned with Cisco Service Provider Cloud Infrastructure design principles:

VXLAN creates aLayer 2 overlay on top of a Layer 3 underlay.

TheVXLAN Network Identifier (VNI)provides a much larger segmentation space than traditional VLANs, enabling multi-tenancy at cloud scale.

Because the underlay is pure Layer 3 (IP routed fabric), VXLAN allows you tointerconnect Layer 2 segments between leaf switches or data centers over an IP/MPLS backbonewithout relying on large Layer 2 domains in the physical network.

Why the options evaluate as follows:

Option A: extends Layer 2 segments across the underlying Layer 3 infrastructure✅This is the core benefit of VXLAN in cloud-scale designs. VXLAN encapsulates Layer 2 frames intoIP/UDP headers, allowing isolated Layer 2 segments (per VNI) to be stretched across a routed IP network. This enables:

Multi-tenant Layer 2 connectivity across a distributed cloud fabric

Mobility of virtual machines or containers while keeping same IP/MAC addressing

Use of an IP-based leaf–spine or service provider underlay for scalability and resiliency

Option B: extends Layer 3 segments across the underlying Layer 2 infrastructure❌This is the opposite of what VXLAN does. VXLAN is explicitlyL2-over-L3, not L3-over-L2. Extending pure Layer 3 segments over Layer 2 is not the VXLAN use case.

Option C: reduces spanning-tree complexity across the Layer 2 infrastructure⚠️(Partially related but not the primary or direct benefit)In modern designs, the underlay isLayer 3 routed, and VXLAN overlays provide logical Layer 2 segments. This designavoids dependence on spanning tree in the fabric, whichindirectlyreduces STP complexity. However, the fundamental, exam-relevant benefit isL2 extension over L3, so C is not the best or most accurate answer compared to A.

Option D: eliminates the need for a Layer 3 underlay in the service provider infrastructure❌VXLAN absolutelyrequiresan IP (Layer 3) underlay for transport. VXLAN tunnels are built over a routed infrastructure (leaf–spine, MPLS/IP core, etc.). It does not remove the need for Layer 3; it depends on it.

Comprehensive and Detailed Explanation

AWSSecurity Groupsact as the primary stateful firewalls for EC2 instances.

To restrict SSH (TCP/22) to a single host (20.20.20.20/32), aSecurity Groupmust be configured with:

Inbound rule: TCP 22

Source: 20.20.20.20/32

ACLs operate at the subnet level but are not used for instance-specific SSH restrictions.

WAF controls HTTP/HTTPS traffic, not SSH.

Resource groups only organize cloud assets.

Thus,Bis the correct solution.

Comprehensive and Detailed Explanation

Cisco Container Platform (CCP), built on Kubernetes orchestration, usesYAMLfiles for:

Cluster configuration

Pod definitions

Network settings

Storage mappings

YAML is the industry-standard declarative syntax for Kubernetes and container orchestration platforms.

HTML, XHTML, and XML are not used for CCP configuration.

Comprehensive and Detailed Explanation From Cisco SP Core Optimization Knowledge

Cisco IOS supportsBGP Multipathfor installing multiple equal-cost BGP routes (both iBGP and eBGP) into the routing table. The correct global BGP command syntax to set the number of allowable parallel BGP paths is:

maximum-paths

For BGP specifically, the form is:

maximum-paths bgp

This enables the router to install up to the specified number of equal-cost BGP routes (iBGP and eBGP) into the RIB and then potentially into the FIB.

Setting:

maximum-paths bgp 6

allowssixparallel ECMP paths learned via BGP—this matches the requirement in the question.

Why the other options are incorrect

B. multipath eibgp 6Not a valid Cisco IOS command.

C. maximum paths bgp routers 6Invalid syntax.

D. maximum-paths eibgp 6The correct keyword isbgp, noteibgp.Cisco does not use “eibgp” in this context; IOS supports BGP multipath across iBGP/eBGP automatically when configured under maximum-paths bgp.

Cisco NSO-based orchestration principles in a multi-vendor environment require:

Service modeling using flexible, reusable YANG models

Abstraction of vendor-specific device differences

Transaction-safe configuration validation and execution

End-to-end automation across lifecycle stages (Day-0, Day-1, Day-N)

Scalability and adaptability for evolving requirements

Option C aligns perfectly with NSO service-modeling approaches:

Service models must be flexible, not rigid, enabling changes as technologies and needs evolve.

The architecture must support continuous refinement, enabling multi-vendor abstraction and lifecycle automation.

This ensures the network evolves seamlessly while remaining stable and automated.

Why the Other Options Are Incorrect

A – Simplified monitoring and post-deployment adjustments do not meet the core need for full lifecycle service modeling and abstraction.

B – Configuring devices individually contradicts the entire purpose of orchestration and abstraction.

D – A static YANG model cannot accommodate multi-vendor environments or future scalability.

Thus, only Option C matches full NSO-capable service modeling requirements.