Cisco 300-420 Bundle

EtherChannel members need compatible Layer 2 settings and negotiated bundling state to represent a correct logical link. “Standardize member configuration and use supported LACP negotiation and consistency checks for the port channel” would remedy that alternative situation, but it would not correct the present issue: without port security or identity-aware access control, a simple access port may learn multiple endpoint MAC addresses without limitation.

“Use a validated multichassis EtherChannel, virtual switching, or routed dual-homing design for platform capabilities” is the supported response when a conventional port channel cannot span unrelated independent switches without a supported multichassis or stacking mechanism. Here the decisive response is “Deploy suitable port security or 802.1X/MAB policies with sensible violation and recovery handling for endpoint types”, so that different intervention does not meet the stated requirement.

Ordinary directed and local broadcasts do not automatically cross routed boundaries, so an explicit authorized delivery design is required. “Design secure supported WoL relays, proxy agents or local management distribution rather than exposing unrestricted broadcasts” applies to that other condition. The reported evidence is a user port should admit one registered device but an unmanaged bridge with several MAC addresses is connected, and the switch admits all sources; this alternative would address the wrong dependency.

A purely hub-and-spoke forwarding policy can add latency and load when the DMVPN design is intended to allow direct spoke shortcuts. “Use a supported DMVPN phase and NHRP routing design that safely establishes eligible spoke-to-spoke tunnels” would remedy that alternative situation, but it would not correct the present issue: dynamic spoke resolution needs correct NHRP network ID, authentication, hub mapping and reachable tunnel source rather than only a live Internet connection.

“Combine supported GRE transport with an appropriate IPsec protection design, or select a secure alternative meeting multicast needs” is the supported response when GRE provides encapsulation for multiple protocols but does not itself encrypt or authenticate payload confidentiality. Here the decisive response is “Align supported NHRP and tunnel registration settings and verify the hub can map the spoke's current public transport address”, so that different intervention does not meet the stated requirement.

An encrypted Internet overlay does not provide the same private carrier connectivity, SLA and traffic-engineering options as a qualified dedicated cloud circuit. “Compare direct cloud private interconnect with managed Internet VPN based on security, bandwidth, route exchange and service commitments” applies to that other condition. The reported evidence is after replacing a branch Internet router, its DMVPN tunnel interface can reach the public network but the spoke no longer appears as registered at the hub; this alternative would address the wrong dependency.

Fabric overlay endpoints require a suitable border function to exchange external route reachability with nonfabric networks. “Evaluate border redundancy, route advertisement scope and external underlay handoff before deployment” would remedy that alternative situation, but it would not correct the present issue: ordinary underlay reachability does not assign endpoint onboarding and VXLAN edge functions to a nonfabric access device.

“Test fabric data-plane MTU and underlay reachability as separate acceptance criteria” is the supported response when fabric overlay encapsulation adds overhead beyond ordinary IP reachability and depends on a healthy L3 underlay. Here the decisive response is “Validate fabric-edge software, port roles and endpoint registration during site migration”, so that different intervention does not meet the stated requirement.

Fabric control-plane endpoint-to-location mapping must reflect movement and be consistent with current host registration. “Monitor control-plane registration freshness and duplicate endpoint identities in multibuilding fabrics” applies to that other condition. The reported evidence is a newly connected access switch is routed to the fabric core but attached endpoints never receive the expected overlay segmentation because the device is not operating as a fabric edge; this alternative would address the wrong dependency.

Random early detection is usually better aligned with responsive TCP queues than with high-priority delay-sensitive voice traffic. “Validate platform queue and drop algorithm selection for each application class” would remedy that alternative situation, but it would not correct the present issue: encryption hides much application payload from intermediate classifiers, so deep packet inspection may not see per-app content inside the tunnel.

“Include the provider QoS contract and trust-domain mapping in WAN migration design packages” is the supported response when DSCP semantics and provider class-of-service mappings are not necessarily preserved across an independent administrative domain. Here the decisive response is “Validate classification location relative to encryption and encapsulation at design time”, so that different intervention does not meet the stated requirement.

Priority queuing alone cannot create bandwidth beyond circuit capacity, and too many concurrent sessions can oversubscribe voice allocation. “Recalculate concurrent-call capacity whenever codec, provider CIR or secondary WAN path changes” applies to that other condition. The reported evidence is an organization classifies applications by payload signatures inside IPsec tunnels and then finds all encrypted business traffic mapped to a single generic class; this alternative would address the wrong dependency.

Ordinary directed and local broadcasts do not automatically cross routed boundaries, so an explicit authorized delivery design is required. “Document WoL security and relay dependencies when redesigning campus routing and NAC controls” would remedy that alternative situation, but it would not correct the present issue: available PoE power budget and per-port capabilities determine whether simultaneous endpoint power requirements can be met.

“Prove peer-link, keepalive and split-brain failure behavior before choosing dual-chassis aggregation” is the supported response when a conventional port channel cannot span unrelated independent switches without a supported multichassis or stacking mechanism. Here the decisive response is “Track real endpoint power profiles and spare capacity during access switch procurement”, so that different intervention does not meet the stated requirement.

Without port security or identity-aware access control, a simple access port may learn multiple endpoint MAC addresses without limitation. “Align MAC limit exceptions with phones, hypervisors and other genuine multi-MAC endpoints” applies to that other condition. The reported evidence is a network redesign adds video endpoints to every access port but budgets only for switch port count, ignoring PoE class and aggregate power draw; this alternative would address the wrong dependency.

DSCP semantics and provider class-of-service mappings are not necessarily preserved across an independent administrative domain. “Negotiate and implement DSCP-to-provider-CoS mapping and verify marking at each trust boundary” would remedy that alternative situation, but it would not correct the present issue: without class-based queue service, different traffic priorities may compete equally under congestion rather than receiving guaranteed minimum allocations.

“Classify and mark before encryption or use supported trusted tunnel metadata and policy-based identification at appropriate endpoints” is the supported response when encryption hides much application payload from intermediate classifiers, so deep packet inspection may not see per-app content inside the tunnel. Here the decisive response is “Implement appropriate CBWFQ or platform-supported scheduler weights after classifying actual traffic”, so that different intervention does not meet the stated requirement.

Random early detection is usually better aligned with responsive TCP queues than with high-priority delay-sensitive voice traffic. “Use appropriate congestion avoidance on suitable best-effort TCP classes and protect voice through controlled priority service” applies to that other condition. The reported evidence is a WAN link has three business traffic classes but the design uses only a best-effort FIFO queue, creating unpredictable delay during peaks; this alternative would address the wrong dependency.

That change concerns is-is adjacency authentication design, where An unprotected adjacency trust boundary can admit unauthorized IS-IS control messages into a routing domain. The reported issue instead stems from: Summary advertisement can attract destinations no longer reachable through the summarizing area, creating a predictable blackhole.

That change concerns eigrp stub branch query containment, where Unbounded EIGRP query scope and nontransit spokes can prolong active route computation across a large topology. In this question the necessary remedy is “Advertise summaries only with valid downstream coverage or an explicitly documented safe discard and failover behavior”, which this alternative does not provide.

That change concerns is-is dual-stack address-family strategy, where Protocol adjacency and IPv4 routes do not alone establish correct IPv6 reachability, interface addressing or address-family support. The observed condition is a regional IS-IS border advertises a broad summary after several internal prefixes have been withdrawn and remote traffic begins hitting an aggregate discard route; this mechanism addresses another problem.

IP-prefix ACLs become brittle when identity and endpoint groups move, while fabric policy can use scalable group-based classification. “Audit SGT classification and policy matrix changes when onboarding new job roles” would remedy that alternative situation, but it would not correct the present issue: fabric overlay multicast support and replication design have specific control and data-plane requirements beyond simple underlay multicast reachability.

“Use virtual-network boundaries for real routing isolation and review any exception-based cross-VN reachability” is the supported response when security group policy alone may not replace full virtual-network level route isolation where separate macrosegments are required. Here the decisive response is “Document platform-specific multicast scalability and multicast-versus-unicast replication tradeoffs”, so that different intervention does not meet the stated requirement.

Identity group classification requires a trusted policy source and onboarding process rather than arbitrary address-based role guessing. “Monitor identity-policy synchronization and handle unknown or unauthenticated endpoint roles explicitly” applies to that other condition. The reported evidence is an enterprise uses multicast video across a campus fabric but assumes ordinary underlay PIM subscriptions automatically deliver overlay multicast groups end to end; this alternative would address the wrong dependency.

Provider-dependent global prefixes may require renumbering when upstream connectivity changes and do not replace a stable local-only design. “Use an appropriately generated unique-local IPv6 prefix for suitable internal services alongside routed global addressing where Internet access is needed” would remedy that alternative situation, but it would not correct the present issue: network dual stacking alone does not add AAAA DNS records, IPv6 listening services, security policy or path validation to existing applications.

“Use a supported startup overload-bit or similar transient-transit suppression design until the node is ready to forward” is the supported response when premature use of a partially ready intermediate system can blackhole transit despite apparently formed control-plane neighbors. Here the decisive response is “Plan application-by-application dual-stack readiness including DNS, access controls, routing, management and rollback verification”, so that different intervention does not meet the stated requirement.

Typical Ethernet SLAAC uses /64 interface identifiers and ordinary host autoconfiguration expectations are not met by arbitrary longer access prefixes. “Allocate /64 prefixes for SLAAC access segments while using more specialized lengths only in supported and justified designs” applies to that other condition. The reported evidence is a company turns on IPv6 routing at its branch WAN edge but assumes every application automatically supports IPv6 even though several server DNS records and firewall policies remain IPv4-only; this alternative would address the wrong dependency.

A hybrid WAN needs explicit route and security decisions because reachability alone does not guarantee sensitive traffic uses approved paths. “Review transport and security policy together whenever adding a new Internet link” would remedy that alternative situation, but it would not correct the present issue: bandwidth alone does not determine application suitability when propagation delay and jitter exceed interactive service limits.

“Test zero-touch onboarding trust and regional orchestrator availability before scaling the fabric” is the supported response when the orchestration function helps WAN edges discover and authenticate to the fabric but should not be placed in the regular data forwarding path. Here the decisive response is “Test delay-sensitive applications on each planned failover path before approving WAN topology”, so that different intervention does not meet the stated requirement.

N-minus-one operation cannot carry combined load if each remaining link lacks spare capacity or business traffic prioritization. “Report both normal and degraded capacity forecasts when approving enterprise WAN budgets” applies to that other condition. The reported evidence is a global contact center selects a very high bandwidth satellite transport for real-time voice even though round-trip latency dominates the application impairment; this alternative would address the wrong dependency.

Local interface carrier may remain up when upstream service fails, so a static route without health tracking can blackhole traffic. “Use supported service probing and tracked next-hop or routing convergence to withdraw an unusable primary path” would remedy that alternative situation, but it would not correct the present issue: multiple logical VLANs on the same physical CE and provider device do not provide independent failure domains.

“Negotiate and implement supported provider service MTU and customer handoff frame sizes including encapsulation requirements” is the supported response when service encapsulation consumes transport overhead and can exceed an underlay MTU that was sized only for native Ethernet payloads. Here the decisive response is “Design separate CE devices, access paths and service-provider terminations in accordance with the required availability objective”, so that different intervention does not meet the stated requirement.

Uncontrolled multihoming can select unpredictable exits and cause asymmetry or suboptimal paths under provider changes. “Define local preference, inbound announcement policy and health tracking based on primary and backup business requirements” applies to that other condition. The reported evidence is a headquarters site hosts revenue-critical services but all WAN connections terminate on one carrier device and one customer-edge router; this alternative would address the wrong dependency.