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Question 320
A wireless access-point refresh increases PoE needs above the available 802.3at class on older switches. Which observed result would most directly prove the design meets the intended goal?
- Permitted uplinks forward under normal operation and converge cleanly on individual link loss.
- Gateway traffic survives a controlled supervisor transition within the approved outage budget.
- Guest clients roam as designed and cannot access restricted enterprise segments.
- Each AP enables its intended radio features at full load without power denial or downshift.
Explanation
Correct Answer
D:Specify access switch PoE capabilities and power budget that support the APs' required negotiated power levels. Verify the resulting network behavior rather than relying only on the saved configuration.
Incorrect Answers
A:This observation relates to a different topology: Multiple access switches connect to one distribution block through independent Layer 2 uplinks with a blocked redundant path. It does not verify the present outcome.
B:This observation relates to a different topology: A remote campus uses two distribution switches and requires nonstop gateway access during a planned supervisor replacement. It does not verify the present outcome.
C:This observation relates to a different topology: A fabric site needs a guest wireless SSID without extending the guest Layer 2 domain across the whole enterprise. It does not verify the present outcome.
Question 321
A partner BGP session accidentally advertises a sensitive 10.0.0.0/8 internal route to an external ASN. Which observed result would most directly prove the design meets the intended goal?
- Branch routers no longer send packets for the retired /24 into a blackhole created by the former summary.
- Both eligible next hops appear in the forwarding table and share representative flows.
- Peer-received advertisements exclude the protected prefix while approved public routes remain.
- Bidirectional test prefixes appear once with predictable origin and no repeated reimport after failover.
Explanation
Correct Answer
C:Apply a scoped outbound prefix filter that blocks private/internal routes from the external BGP adjacency. Verify the resulting network behavior rather than relying only on the saved configuration.
Incorrect Answers
A:This observation relates to a different topology: A campus advertises a /18 summary into the WAN but has no route for one constituent /24 after a building is decommissioned. It does not verify the present outcome.
B:This observation relates to a different topology: A campus border is configured with two equal-cost external BGP paths but only one is installed for traffic forwarding. It does not verify the present outcome.
D:This observation relates to a different topology: Branch A and B redistribute external BGP into OSPF, then advertise resulting routes back into BGP at the opposite edge. It does not verify the present outcome.
Question 322
A routing telemetry client assumes every operational counter supports on-change updates and receives no updates on one platform. Which observed result would most directly prove the design meets the intended goal?
- Data volumes fall while five-minute trend accuracy still meets planning requirements.
- Subscription updates decode into typed intended metrics and preserve their source paths.
- The receiver obtains the expected measurement updates for every required signal.
- The collector reads comparable interface fields from Cisco and non-Cisco devices using supported model paths.
Explanation
Correct Answer
C:Select subscription modes according to the actual leaf and device support, using periodic for counters when necessary. Verify the resulting network behavior rather than relying only on the saved configuration.
Incorrect Answers
A:This observation relates to a different topology: A global WAN telemetry system publishes a complete 10,000-interface snapshot every 100 ms although the target is only five-minute capacity planning. It does not verify the present outcome.
B:This observation relates to a different topology: A telemetry receiver supports gRPC but cannot decode the device's gNMI JSON_IETF path data and classifies every update as malformed. It does not verify the present outcome.
D:This offered choice, “The collector reads comparable interface fields from Cisco and non-Cisco devices using supported model paths”, addresses a separate concern. That option relates to this separate design case: A multivendor enterprise wants one consistent YANG representation for interface operational counters but each platform exposes vendor-specific native trees. It does not answer the current requirement.
Question 323
A WAN team assumes DWDM wavelength multiplexing itself supplies packet-level route isolation between tenants. Which observed result would most directly prove the design meets the intended goal?
- Existing permitted edge-to-edge tunnels continue carrying traffic across a management-plane interruption where supported.
- Edges establish controller sessions and exchange authorized OMP reachability while the transport remains reachable.
- Services over the optical circuit remain isolated by the appropriate higher-layer controls.
- The branch establishes the required controlled overlay sessions without depending on unsupported unsolicited inbound access.
Explanation
Correct Answer
C:Separate optical multiplexing requirements from routing or Ethernet tenant segmentation carried over the wavelengths. Verify the resulting network behavior rather than relying only on the saved configuration.
Incorrect Answers
A:This observation relates to a different topology: A multisite SD-WAN deployment uses one manager for configuration and assumes manager reachability is necessary for every packet of user data. It does not verify the present outcome.
B:This observation relates to a different topology: SD-WAN edges register to the validator but receive no OMP route updates from the controller, and the team claims the underlay is broken. It does not verify the present outcome.
D:This observation relates to a different topology: An industrial site uses 4G LTE as primary WAN, and its routing team assumes public inbound addresses remain reachable through carrier-grade NAT. It does not verify the present outcome.
Question 324
A campus uses DSCP EF for voice signaling, voice media, and backup traffic, causing priority queue overload. Which observed result would most directly prove the design meets the intended goal?
- Control-plane adjacencies and monitoring remain stable during representative congestion.
- Priority queuing protects genuine voice media while backup traffic no longer occupies the strict-priority class.
- Voice delay stays within SLA during video bursts while other classes retain scheduled service.
- All essential classes receive their planned treatment without violating actual egress capacity.
Explanation
Correct Answer
B:Classify traffic by actual application need and reserve EF treatment for suitable expedited traffic. Verify the resulting network behavior rather than relying only on the saved configuration.
Incorrect Answers
A:This observation relates to a different topology: A campus QoS policy gives low priority to routing keepalives and network monitoring, and routing adjacencies flap during congestion. It does not verify the present outcome.
C:This observation relates to a different topology: Video and voice both use one strict-priority queue, causing voice jitter when video surges. It does not verify the present outcome.
D:This observation relates to a different topology: A switch QoS scheduler guarantees 30% to backup traffic and 80% to voice under full congestion, exceeding possible link capacity. It does not verify the present outcome.
Question 325
Two campus VRRP gateways both claim master after their shared advertisement path is partitioned, and clients receive inconsistent ARP responses. Which observed result would most directly prove the design meets the intended goal?
- Exactly one intended master serves the virtual gateway in stable conditions and transitions during failure.
- Probes to live destinations follow correct routes while the decommissioned /24 is no longer misdirected.
- Encapsulated end-to-end test packets pass between fabric edges without fragmentation blackholes.
- Changes to one tenant's routes do not leak or alter the other's forwarding state.
Explanation
Correct Answer
A:Correct VRRP group identity, priorities, advertisement reachability, and L2 path consistency. Verify the resulting network behavior rather than relying only on the saved configuration.
Incorrect Answers
B:This observation relates to a different topology: A site cutover retains a withdrawn /24 under an unchanged /20 campus summary and traffic follows an obsolete transit path. It does not verify the present outcome.
C:This observation relates to a different topology: Fabric edge nodes encapsulate packets, but the underlay path MTU is too small for added VXLAN overhead. It does not verify the present outcome.
D:This observation relates to a different topology: A public safety campus requires independent operations from a corporate tenant even when both use the same distribution hardware. It does not verify the present outcome.
Question 326
An EIGRP core has routes stuck active after one WAN path fails and queries spread into many remote sites. Which observed result would most directly prove the design meets the intended goal?
- Hubs avoid querying through the branch as a transit path and branch-local prefixes remain visible.
- Failed-route convergence completes without broad stuck-in-active propagation.
- The neighbors reach FULL and application packets traverse without fragmentation problems.
- Clients retain enough independent eligible paths to support the agreed failover policy.
Explanation
Correct Answer
B:Apply EIGRP summarization, stub boundaries, and reliable connectivity to limit query scope. Verify the resulting network behavior rather than relying only on the saved configuration.
Incorrect Answers
A:This observation relates to a different topology: A branch EIGRP router advertises remote routes back into its hub and occasionally becomes a transit path between hubs. It does not verify the present outcome.
C:This observation relates to a different topology: Two OSPF neighbors on a routed core link are stuck in EXSTART/EXCHANGE and one endpoint uses an incompatible MTU. It does not verify the present outcome.
D:This observation relates to a different topology: An iBGP route reflector sees several candidate routes to the same destination but advertises only its best path to clients. It does not verify the present outcome.
Question 327
An NSF-capable router pair loses a control-plane process briefly and the design assumes all neighboring routers will preserve forwarding. Which observed result would most directly prove the design meets the intended goal?
- Control-plane endpoint mappings resolve and separate packet captures show VXLAN data forwarding between fabric edges.
- Intersite overlay flows survive the engineered path and meet their measured size and latency limits.
- Endpoint moves are learned through the surviving control-plane node and authorized traffic resumes.
- Neighbor relationships recover while supported forwarding state remains stable during the tested restart.
Explanation
Correct Answer
D:Plan NSF graceful-restart interoperability with compatible neighbors and realistic convergence timeouts. Verify the resulting network behavior rather than relying only on the saved configuration.
Incorrect Answers
A:This observation relates to a different topology: An SD-Access architect assumes the fabric's LISP control plane transports all user packets like a data-plane tunnel. It does not verify the present outcome.
B:This observation relates to a different topology: A design extends SDA fabric across buildings on a WAN with 1500-byte MTU and assumes local campus performance will continue unchanged. It does not verify the present outcome.
C:This observation relates to a different topology: A fabric control-plane node becomes unavailable and endpoint mobility updates stop at one campus site. It does not verify the present outcome.
Question 328
A PIM-SM domain has active receivers but no working rendezvous-point reachability for new source registration. Which observed result would most directly prove the design meets the intended goal?
- Packets arriving on incorrect RPF interfaces are rejected and legitimate receiver traffic passes.
- Receiver ports are present in membership tables and only eligible ports receive the stream.
- Sources registered in either domain become discoverable to intended remote receivers.
- New sources register and receiver joins build the intended multicast distribution tree.
Explanation
Correct Answer
D:Design reliable RP placement or supported RP redundancy with consistent mapping. Verify the resulting network behavior rather than relying only on the saved configuration.
Incorrect Answers
A:This observation relates to a different topology: A multicast source is reachable through an interface other than the one receiving the packet, but the router still forwards it to all receivers. It does not verify the present outcome.
B:This observation relates to a different topology: A multicast network has active PIM neighbors but one edge switch suppresses IGMP reports after an access-layer topology change. It does not verify the present outcome.
C:This observation relates to a different topology: Two independent PIM-SM domains each use local rendezvous points but remote sources must be discovered across the domains. It does not verify the present outcome.
Question 329
A new SD-WAN site has a single edge appliance and single underlay yet is approved as redundant because controllers run in different data centers. Which observed result would most directly prove the design meets the intended goal?
- The branch switches to the secondary circuit within the required service recovery interval.
- Protected optical channels carry authorized client services with measured bit-error and failover performance.
- The site retains approved application reachability after losing one WAN edge or carrier path.
- Guest prefixes and traffic stay isolated from production routes and data tunnels.
Explanation
Correct Answer
C:Provide independent edge and transport paths when required; treat controller redundancy as a separate failure domain. Verify the resulting network behavior rather than relying only on the saved configuration.
Incorrect Answers
A:This observation relates to a different topology: An enterprise's primary WAN circuit fails but BGP route withdrawal is delayed while the underlay interface remains up. It does not verify the present outcome.
B:This observation relates to a different topology: Several data centers need high-capacity optical transport over metropolitan dark fiber without converting each tenant VLAN to an IP tunnel. It does not verify the present outcome.
D:This observation relates to a different topology: An SD-WAN fabric routes guest traffic into the production VPN because a new edge reused the corporate service VPN identifier. It does not verify the present outcome.
Question 330
A campus design requires both distribution uplinks active but the chosen topology uses classic STP on all Layer 2 connections. Which observed result would most directly prove the design meets the intended goal?
- Changes to one tenant's routes do not leak or alter the other's forwarding state.
- Gateway traffic survives a controlled supervisor transition within the approved outage budget.
- Both paths carry approved traffic and a member failure has no broad STP reconvergence.
- Permitted uplinks forward under normal operation and converge cleanly on individual link loss.
Explanation
Correct Answer
C:Use a supported multi-chassis EtherChannel or routed-access design to make redundancy active without a spanning-tree loop. Verify the resulting network behavior rather than relying only on the saved configuration.
Incorrect Answers
A:This observation relates to a different topology: A public safety campus requires independent operations from a corporate tenant even when both use the same distribution hardware. It does not verify the present outcome.
B:This observation relates to a different topology: A remote campus uses two distribution switches and requires nonstop gateway access during a planned supervisor replacement. It does not verify the present outcome.
D:This observation relates to a different topology: Multiple access switches connect to one distribution block through independent Layer 2 uplinks with a blocked redundant path. It does not verify the present outcome.
Designing Cisco Enterprise Networks (ENSLD) (300-420) Practice Tests
