300-540 Designing and Implementing Cisco Service Provider Cloud Network Infrastructure (SPCNI v1.0) Questions and Answers

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.

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 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.

Cisco NFVIS follows strict security controls. After a fresh deployment:

Thedefault admin credentials are considered insecure.

NFVIS requires the administrator toreset the default password on first login(typically via console or SSH).

Until the password is changed,REST API and web-portal access are denied, and attempts to access the portal or API returnHTTP 401 Unauthorized, even if the default credentials are provided.

This mechanism prevents use of factory-default passwords in production and is explicitly documented as a mandatory post-install step.

The other options are not the cause of a 401 error:

Enabling portal via SSH (B) is not required; HTTPS access is enabled by default once credentials are valid.

Restarting Tomcat (C) would address service availability issues (e.g., 5xx errors), not authentication.

Browser certificates (D) affect trust warnings (e.g., HTTPS certificate errors), not 401 Unauthorized.

Comprehensive and Detailed Explanation

In Cisco high-availability LAN gateway designs, the requirement is:

Multiple L3 gateways sharing avirtual MAC and virtual IP

Ability toload balanceacross multiple active gateways

Capability toseamlessly take overgateway forwarding during a failure

Among Cisco First Hop Redundancy Protocols (FHRPs):

HSRP→ Active/standby only

VRRP→ Active/standby only

GLBP (Gateway Load Balancing Protocol)→The only FHRP providing active/active load balancing

GLBP allows multiple routers to share:

Acommon virtual IP

Multiplevirtual MAC addresses

Multipleactive forwardersthat load-balance end hosts

Automatic failover if any gateway fails

Thus, GLBP is the only correct protocol matching the requirement forredundant default gateways with load balancing and shared MAC addressing.

Comprehensive and Detailed Explanation

Cisco NFVIS logging levels (from lowest to highest):

critical

error

warning

info

debug←highest verbosity

To capture maximum diagnostic detail, engineers must enabledebuglogging on theoperational log type, which records system activity and runtime behavior.

Thus the correct command is:

system set-log logtype operational level debug

This provides the deepest troubleshooting visibility.

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.

Comprehensive and Detailed Explanation

AnAPI logic flawis a weakness in the API’sbusiness logic— not in encryption or transport security. It occurs when:

API functions are misused

Business rules are bypassed

Security validation is missing

Workflow logic is incorrect

These issues cannot be solved through encryption (at rest or in transit). They require:

✔Vulnerability remediation

✔Fixing API code logic

✔Updating API validation, flow control, and authentication logic

Thus the correct answer isC. Remediation of vulnerabilities.

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.

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.

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.

On R1 the configuration (simplified) is:

ip domain lookup

ip domain name ccnp.test

ip host www.ccnp.test 10.1.1.1 10.2.1.1 10.3.1.1

The ip host command statically maps the hostname www.ccnp.test

to three IP addresses. By default, Cisco IOS will always return these IP addresses to DNS queries in the same order they are configured (10.1.1.1, then 10.2.1.1, then 10.3.1.1). This means that clients will always attempt 10.1.1.1 first and will not achieve per-query load balancing across all three servers.

To enable DNS-based load balancing so that each successive query rotates the order of the addresses, Cisco IOS provides the command:

ip domain round-robin

This command enables round-robin rotation of multiple A records associated with a single hostname defined by ip host. With this feature enabled:

1st query: response order 10.1.1.1, 10.2.1.1, 10.3.1.1

2nd query: response order 10.2.1.1, 10.3.1.1, 10.1.1.1

3rd query: response order 10.3.1.1, 10.1.1.1, 10.2.1.1

Clients will typically try the first IP address in the list and use the others if the first one fails, exactly matching the requirement.

Why other options are incorrect:

A. ip domain retry 3 controls how many times the router retries DNS queries to a server; it does not control the order of multiple A records.

C. ip dns server turns the router into a DNS server but does not itself provide round-robin behavior for statically defined hosts.

D. maximum-paths 3 is a routing (IP forwarding) parameter for equal-cost multipath, unrelated to DNS resolution.

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.

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.

In an NFV environment following Cisco NFV Infrastructure and ETSI MANO architecture, the onboarding workflow for VNF deployment follows this high-level order:

Define VNF descriptors (VNFD and NSD)– Includes implementation details and service definitions.

Prepare virtual machine resources– Flavor, image, CPU/memory/storage, and placement.

Define the NFV network– This step builds the underlay/overlay connectivity needed for the VNF.– It includes virtual network creation, interfaces, VLs (Virtual Links), connection points, and mapping into OpenStack (Neutron networks, subnets, ports).– No VNF can be deployed until the NFV service networks (management, control, data, HA) are defined.

Apply Day-0 configuration– Bootstrapping/initial config.

Apply Day-1 operational characteristics– Routing, services, policies.

Configure operational monitoring (KPIs)– Performance and fault measurements.

Since the question states“after the VM resources are prepared”, the next mandatory stage is defining the virtual network connectivity on which the VNFs will operate.