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

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:

Cisco+ Hybrid Cloud is Cisco’s as-a-service consumption model that offers pay-as-you-go infrastructure. For ahybrid workplace, the focus is on giving users secure desktop environments from anywhere, with the ability torapidly deployandscale up or downbased on the number of users or partners.

Cisco+Hybrid Cloud for Virtual Desktop Infrastructure (VDI)specifically delivers desktop and app workspaces as an on-demand service. It allows partners to consume desktops elastically, paying for capacity as needed and scaling the underlying compute, storage, and networking without rebuilding the environment.

Bare Metal Compute and Virtualization offers flexible infrastructure but are aimed at app/workload hosting rather than user desktop workspaces.

Service Provider Networking addresses network services, not end-user hybrid workplace desktops.Therefore, for a pay-as-you-go, rapidly deployable, elastic solution in a hybrid workplace,Cisco+ Hybrid Cloud for Virtual Desktop Infrastructureis the correct choice.

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 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.

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 the diagram, thePE and R2, R3, R4, R5belong toAS 100. The PE router runs BGP processAS 100, so its BGP configuration must start with:

router bgp 100

To performiBGP multipath load sharingacross three equal-cost internal BGP paths, BGP must be instructed to keep and use multiple iBGP paths in the routing table. This is done with:

router bgp 100

maximum-paths ibgp 3

maximum-paths ibgp 3 tells BGP to install up tothreeiBGP paths to the same prefix, enabling CEF to load-share across those paths.

router bgp 100 is required because the PE is inAS 100, not 101.

Other options:

ip load-sharing per-destination affects CEF behavior but does not enable BGP iBGP multipath by itself and is not specific to three iBGP paths.

ip load-sharing ibgp 3 is not a valid IOS BGP command.

router bgp 101 would configure the wrong AS and break the iBGP relationships shown in AS-100.

Thus, the correct commands on the PE to achieve iBGP multipath load sharing over the three internal paths aremaximum-paths ibgp 3androuter bgp 100, corresponding toA and E.

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.

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.

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.

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

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 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.

InCisco Enterprise NFVIS, time synchronization is configured using thesystem time ntpcommand structure. NFVIS requires a primary and optionally a backup NTP server to maintain accurate system time for the hypervisor and guest VMs.

Correct NFVIS command syntax for NTP configuration:

system time ntp preferred_server This command configures thepreferred (primary)NTP server used for system clock synchronization.

system time ntp backup_server This command configures thebackupNTP server, which the system uses if the primary becomes unreachable.

These two commands match Cisco NFVIS time-configuration behavior described in NFV infrastructure design and implementation guidelines.

Why the Correct Answers Are A and E

Option A: system time ntp preferred_server 192.168.1.1

This properly configures the primary NTP server in NFVIS. The preferred server is always the first choice for time synchronization.

Option E: system time ntp backup_server 192.168.2.1

This correctly configures the backup NTP server. If the preferred server fails, NFVIS automatically falls back to the backup server.

Both commands directly match NFVIS’s NTP command hierarchy and are the only ones that correctly apply to NFVIS.

Why the Other Options Are Not Correct

Option Buses utils ntp, which is not an NFVIS command.

Option Csets manual time and does not configure NTP servers.

Option Dalso uses the utils ntp syntax, which applies to other Cisco platforms but not NFVIS.

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.

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.