Cisco 300-420 Bundle

VPN session status can be healthy while mismatched crypto ACLs or traffic selectors omit the application flow. “Update both peers' protected prefix definitions and routing design with least-privilege permitted flows” would remedy that alternative situation, but it would not correct the present issue: traditional point-to-point encryption tunnel meshes may add unnecessary topology and scale complexity for a trusted private routed underlay.

“Budget tunnel overhead, validate tunnel MTU/MSS adjustment and preserve necessary ICMP feedback” is the supported response when encapsulation and encryption overhead reduce effective path MTU, and missing PMTUD control messages can stall large packets. Here the decisive response is “Evaluate supported GET VPN group key distribution and policy design where technology and business requirements fit”, so that different intervention does not meet the stated requirement.

Tenant route separation blocks cross-VPN reachability until carefully controlled route-target import/export rules make the intended service available. “Design an approved extranet or shared-services VPN import/export model with explicit prefix filters and security enforcement” applies to that other condition. The reported evidence is a corporate private MPLS WAN needs IP payload confidentiality across many sites without forcing ordinary site-to-site traffic through a tunnel hub; this alternative would address the wrong dependency.

Without class-based queue service, different traffic priorities may compete equally under congestion rather than receiving guaranteed minimum allocations. “Implement appropriate CBWFQ or platform-supported scheduler weights after classifying actual traffic” would remedy that alternative situation, but it would not correct the present issue: average throughput can hide instantaneous bursts and delay variation that disrupt real-time media even when link utilization seems moderate.

“Place supported ingress policing and remarking at appropriate boundaries and egress queuing at the actual bottleneck” is the supported response when input classification and policing operate on traffic entering an interface, while output scheduling applies to egress congestion. Here the decisive response is “Reserve suitable queue and burst tolerance based on codec behavior, media priority and empirically observed peak load”, so that different intervention does not meet the stated requirement.

Traffic classification order and policy constructs can cause broad conditions to overshadow intended more-specific class handling. “Refine class-map criteria and supported policy evaluation to classify the real-time flows before generic groups” applies to that other condition. The reported evidence is interactive training video experiences brief rate bursts, and engineers allocate only average bitrate with no jitter or loss allowance across the WAN; this alternative would address the wrong dependency.

Using only the affected data-plane overlay for operational access can eliminate remote troubleshooting when the fabric fails. “Include recovery-path isolation and management access policy in branch deployment standards” would remedy that alternative situation, but it would not correct the present issue: logical transport labels or TLOCs do not inherently represent independent circuits, carrier facilities or last-mile paths.

“Separate management-plane restoration targets from traffic-plane availability objectives in SLA design” is the supported response when management availability and existing data-plane forwarding have different dependencies, while loss of manageability remains an operational risk. Here the decisive response is “Inventory the physical dependencies of each SD-WAN color before declaring path redundancy”, so that different intervention does not meet the stated requirement.

Data-plane tunnel presence does not guarantee that control-plane route advertisement and segmentation policy deliver needed service prefixes. “Audit route policy and tenant VPN scoping when adding branches to SD-WAN regions” applies to that other condition. The reported evidence is two SD-WAN colors are configured for a branch but both use the same physical Internet interface and carrier, despite a requirement for physical WAN diversity; this alternative would address the wrong dependency.

Multiple logical VLANs on the same physical CE and provider device do not provide independent failure domains. “Track physical and provider diversity from rack power to metro access rather than counting only service circuit IDs” would remedy that alternative situation, but it would not correct the present issue: uncontrolled multihoming can select unpredictable exits and cause asymmetry or suboptimal paths under provider changes.

“Test off-site failure scenarios where the local modem stays up rather than only unplugging the branch cable” is the supported response when local interface carrier may remain up when upstream service fails, so a static route without health tracking can blackhole traffic. Here the decisive response is “Validate provider policy and route advertisement behavior after every BGP contract change”, so that different intervention does not meet the stated requirement.

Shortcut VPN topology changes can bypass required inspection if the WAN policy assumes every flow transits a central hub. “Review VPN shortcut and route optimization features whenever security architecture mandates central inspection” applies to that other condition. The reported evidence is an enterprise connects to two providers and wants symmetric business traffic behavior but simply allows both defaults with no designed routing policies; this alternative would address the wrong dependency.

NETCONF and RESTCONF share model-driven concepts but use different protocol transports, operation semantics and session behavior. “Run interoperability tests for protocol authentication, payload encoding and error handling before deployment” would remedy that alternative situation, but it would not correct the present issue: on-change subscriptions report eligible state changes, not necessarily uniformly spaced observations required for some time-series analytics.

“Measure both publication and collector overhead rather than assuming every telemetry stream is automatically cheaper” is the supported response when repeated broad request-response polling can impose higher overhead than selective model-driven subscription updates for suitable telemetry. Here the decisive response is “Document analytics cadence requirements before selecting telemetry subscription mode”, so that different intervention does not meet the stated requirement.

Coarse periodic publication can delay visibility of short state transitions and is not equivalent to supported event-driven on-change reporting. “Test event delivery under frequent flaps and avoid overwhelming collection systems with unbounded updates” applies to that other condition. The reported evidence is a capacity planning service needs a stable one-minute time series but engineers configure only on-change updates and complain that unchanged gauges disappear; this alternative would address the wrong dependency.

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” would remedy that alternative situation, but it would not correct the present issue: logical dual-circuit contracts may share a physical access path and suffer a common-cause outage.

“Use a supported DMVPN phase and NHRP routing design that safely establishes eligible spoke-to-spoke tunnels” is the supported response when a purely hub-and-spoke forwarding policy can add latency and load when the DMVPN design is intended to allow direct spoke shortcuts. Here the decisive response is “Choose WAN edge circuits with validated last-mile, provider and facility diversity where the service recovery target requires it”, so that different intervention does not meet the stated requirement.

Dynamic spoke resolution needs correct NHRP network ID, authentication, hub mapping and reachable tunnel source rather than only a live Internet connection. “Align supported NHRP and tunnel registration settings and verify the hub can map the spoke's current public transport address” applies to that other condition. The reported evidence is a branch selects two MPLS circuits from the same provider that terminate in one local trench and claims the resulting design is carrier diverse; this alternative would address the wrong dependency.

Local breakout bypasses central inspection unless equivalent secure edge controls and policy are deliberately placed. “Design approved branch egress security with local firewall, cloud security service or appropriate service chaining” would remedy that alternative situation, but it would not correct the present issue: an unsegmented overlay routing context can make trust-boundary errors more likely even if some edge access rules exist.

“Choose a supported multicast distribution and replication approach with measured receiver count and transport constraints” is the supported response when naive unicast replication can consume excessive WAN capacity, while multicast support depends on platform and overlay design. Here the decisive response is “Use separate service VPN or VRF contexts with explicit leak rules and security policy at authorized shared-service borders”, so that different intervention does not meet the stated requirement.

Static transport preference does not substitute for application-aware path decisions using measured latency, loss and jitter. “Create supported application-aware routing policy with validated SLA class thresholds and fallback behavior” applies to that other condition. The reported evidence is guest Internet access and regulated internal branch traffic share one SD-WAN service VPN and use ordinary address filters for separation; this alternative would address the wrong dependency.

Physical redundancy does not imply control-plane equal-cost path installation or useful flow distribution. “Align appropriate IGP costs and supported equal-cost multipath settings with capacity and symmetric path requirements” would remedy that alternative situation, but it would not correct the present issue: high session counts and excessively aggressive timers can exhaust control resources and cause false routing flaps.

“Export only authorized service prefixes and apply necessary packet access restrictions at the shared-services border” is the supported response when unfiltered inter-VRF route leaking can undermine segmentation even if each tenant has its own routing instance. Here the decisive response is “Model required convergence classes and scale BFD deployment selectively on critical routed interfaces”, so that different intervention does not meet the stated requirement.

A summary advertised by a border without valid components can attract and blackhole traffic during partial network failures. “Tie aggregate advertisement to required downstream reachability or redesign summarization and redundancy accordingly” applies to that other condition. The reported evidence is a design mandates subsecond link failure reaction on hundreds of campus peers and enables aggressive BFD for every adjacency without capacity estimation; this alternative would address the wrong dependency.

Protocol adjacency and IPv4 routes do not alone establish correct IPv6 reachability, interface addressing or address-family support. “Implement supported IS-IS IPv6 reachability with interface family configuration and consistent topology preferences” would remedy that alternative situation, but it would not correct the present issue: summary advertisement can attract destinations no longer reachable through the summarizing area, creating a predictable blackhole.

“Deploy supported IS-IS authentication with coordinated algorithms and keys and restrict peers to intended segments” is the supported response when an unprotected adjacency trust boundary can admit unauthorized IS-IS control messages into a routing domain. Here the decisive response is “Advertise summaries only with valid downstream coverage or an explicitly documented safe discard and failover behavior”, so that different intervention does not meet the stated requirement.

Unbounded EIGRP query scope and nontransit spokes can prolong active route computation across a large topology. “Declare eligible nontransit branches as EIGRP stubs and summarize at appropriate aggregation points with verified alternate paths” applies to that other condition. The reported evidence 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 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: the orchestration function helps WAN edges discover and authenticate to the fabric but should not be placed in the regular data forwarding path.

“Test delay-sensitive applications on each planned failover path before approving WAN topology” is the supported response when bandwidth alone does not determine application suitability when propagation delay and jitter exceed interactive service limits. Here the decisive response is “Test zero-touch onboarding trust and regional orchestrator availability before scaling the fabric”, so that different intervention does not meet the stated requirement.

Multihoming and address translation must account for both directions; outbound route changes alone may not preserve return paths. “Test full transactions and reverse paths, not only traceroutes leaving the branch WAN edge” applies to that other condition. The reported evidence is a design document treats Cisco SD-WAN orchestration as the same component that carries every branch's user payload rather than enabling secure device discovery; this alternative would address the wrong dependency.

That change concerns udld fiber bidirectional verification, where Physical link-up is insufficient to guarantee bidirectional signal integrity, which can affect control-plane protocols and forwarding. The reported issue instead stems from: A per-VLAN spanning-tree model scales protocol state with VLAN count and may become less efficient than suitable aggregated instances.

That change concerns stp root guard toward untrusted switch, where Superior BPDUs on an untrusted downstream link can alter STP root selection unless the boundary is protected. In this question the necessary remedy is “Assess MST or Layer 3 access boundaries against actual traffic steering and availability requirements”, which this alternative does not provide.

That change concerns mst region boundary mismatch, where MST region membership requires consistent region identifier, revision and VLAN mapping rather than matching only some VLAN names. The observed condition is a campus uses hundreds of VLANs with distinct rapid spanning-tree instances and experiences growing CPU and change-control complexity; this mechanism addresses another problem.