Cisco 300-420 Bundle

Layer 1 carrier state may not reveal a downstream path failure and slow neighbor detection extends blackhole time. “Deploy supported BFD for the intended OSPF peers, validate timers against platform capacity and test false-positive risk” would remedy that alternative situation, but it would not correct the present issue: graceful restart depends on both peers' supported capabilities and bounded stale-route handling, not merely a routing session name.

“Evaluate path attributes and supported multipath settings, then choose a design that preserves deterministic failover” is the supported response when BGP additional paths must satisfy supported multipath eligibility rules and configured maximum-path policy to share traffic. Here the decisive response is “Enable and verify supported graceful restart with sensible stale timers and failover safeguards where appropriate”, so that different intervention does not meet the stated requirement.

An IPv4-only underlay cannot natively carry IPv6 forwarding without an overlay or other transition capability. “Use a supported IPv6-over-IPv4 tunnel with correct endpoint reachability, encapsulation security and effective MTU” applies to that other condition. The reported evidence is a provider BGP edge restarts its control process and a peer immediately removes all routes even though the design expects transient forwarding continuity; this alternative would address the wrong dependency.

Conventional iBGP full mesh grows quadratically and becomes costly to configure, observe and recover. “Test reflection path diversity and redundant reflector failure modes before retiring full-mesh peers” would remedy that alternative situation, but it would not correct the present issue: external Type 2 cost behavior does not account for internal cost in the same way as Type 1 when external metrics differ.

“Keep OSPF area allocation aligned with IPAM aggregation boundaries across expansion projects” is the supported response when a fragmented area-address plan and missing ABR inter-area summarization cause avoidable detailed LSAs to propagate. Here the decisive response is “Document OSPF external metric type as part of every redistribution design review”, so that different intervention does not meet the stated requirement.

OSPF hierarchical inter-area connectivity depends on a stable backbone design and resilient area border connectivity. “Evaluate area zero failure domains and ABR diversity before placing mission-critical applications in branch areas” applies to that other condition. The reported evidence is a redistribution design sends external OSPF Type 2 routes across sites with very different internal transit costs, yet expects remote sites to prefer the closest exit; this alternative would address the wrong dependency.

That change concerns layer 2 vpn transparent branch extension, where An MPLS Layer 3 VPN routes IP among separated CE networks rather than delivering a transparent Layer 2 Ethernet service. The reported issue instead stems from: Mobile backup is useful only if real coverage, policy, cost and failure independence support required branch services.

That change concerns metro ethernet multi site scaling, where Multipoint Ethernet services and many independent E-Line circuits have different Layer 2 forwarding and spanning-tree implications. In this question the necessary remedy is “Design cellular failover with tested signal strength, provider diversity, data-plan capacity and selective critical traffic routing”, which this alternative does not provide.

That change concerns mpls layer 3 vpn tenant separation, where A shared provider routing domain cannot preserve independent overlapping tenant address spaces and route targets without isolation. The observed condition is a remote retail site uses a single fixed broadband circuit and proposes 5G backup without checking data caps, radio conditions or carrier diversity; this mechanism addresses another problem.

The orchestration function helps WAN edges discover and authenticate to the fabric but should not be placed in the regular data forwarding path. “Design supported Catalyst SD-WAN orchestrator reachability and certificate trust separately from data-plane transport tunnels” would remedy that alternative situation, but it would not correct the present issue: an encrypted Internet overlay does not provide the same private carrier connectivity, SLA and traffic-engineering options as a qualified dedicated cloud circuit.

“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 “Compare direct cloud private interconnect with managed Internet VPN based on security, bandwidth, route exchange and service commitments”, so that different intervention does not meet the stated requirement.

GRE provides encapsulation for multiple protocols but does not itself encrypt or authenticate payload confidentiality. “Combine supported GRE transport with an appropriate IPsec protection design, or select a secure alternative meeting multicast needs” applies to that other condition. The reported evidence is a regulated enterprise runs latency-sensitive cloud workloads but routes all traffic through a public Internet VPN and needs predictable private provider connectivity; this alternative would address the wrong dependency.

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” would remedy that alternative situation, but it would not correct the present issue: input classification and policing operate on traffic entering an interface, while output scheduling applies to egress congestion.

“Reserve suitable queue and burst tolerance based on codec behavior, media priority and empirically observed peak load” is the supported response when average throughput can hide instantaneous bursts and delay variation that disrupt real-time media even when link utilization seems moderate. Here the decisive response is “Place supported ingress policing and remarking at appropriate boundaries and egress queuing at the actual bottleneck”, so that different intervention does not meet the stated requirement.

A syntactically installed QoS policy does not establish that actual applications match intended classes or receive required forwarding treatment. “Run controlled traffic tests and inspect class and queue counters, delay and drop statistics end to end” applies to that other condition. The reported evidence is a campus operator attaches an output queue policy to a branch WAN interface but expects it to police inbound untrusted DSCP markings from the carrier; this alternative would address the wrong dependency.

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” would remedy that alternative situation, but it would not correct the present issue: fabric control-plane endpoint-to-location mapping must reflect movement and be consistent with current host registration.

“Validate fabric-edge software, port roles and endpoint registration during site migration” is the supported response when ordinary underlay reachability does not assign endpoint onboarding and VXLAN edge functions to a nonfabric access device. Here the decisive response is “Monitor control-plane registration freshness and duplicate endpoint identities in multibuilding fabrics”, so that different intervention does not meet the stated requirement.

Fabric overlay encapsulation adds overhead beyond ordinary IP reachability and depends on a healthy L3 underlay. “Test fabric data-plane MTU and underlay reachability as separate acceptance criteria” applies to that other condition. The reported evidence is a fabric edge learns an endpoint address but forwards to an old location after the endpoint moves between buildings because its mapping data is stale; 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: independent rendezvous points do not automatically exchange all active-source information across ASM multicast domains.

“Design SSM-compatible group range, sender addressing and receiver IGMPv3 support end to end” is the supported response when source-specific multicast applications need supported source-aware receiver membership signaling, commonly IGMPv3 for IPv4. Here the decisive response is “Use supported MSDP or a suitable alternative interdomain multicast design with appropriate RP and source policies”, so that different intervention does not meet the stated requirement.

ASM initially uses a shared RP tree and may switch to source-specific shortest-path forwarding according to design and platform behavior. “Evaluate supported SPT threshold and source-tree design for bandwidth and latency goals without creating RPF inconsistencies” applies to that other condition. The reported evidence is two autonomous multicast domains each run PIM sparse mode with separate RPs, but receivers in one domain cannot discover active senders in the other; this alternative would address the wrong dependency.

RESTCONF uses resource-oriented HTTP methods with defined read and write semantics, so GET is not an appropriate configuration write operation. “Use supported RESTCONF PATCH, PUT or POST methods at correct YANG resource paths with authorization and content types” would remedy that alternative situation, but it would not correct the present issue: logical network separation on one physical direct-connect facility does not eliminate common power, provider or meet-me-room failures.

“Integrate MPLS L3VPN with approved cloud private routing and select per-tenant VRF and gateway route policies” is the supported response when private transport does not automatically enforce tenant segmentation or prevent unintended route exchange into cloud environments. Here the decisive response is “Design redundant cloud interconnects with suitable facility diversity, BGP and controlled Internet or secondary private fallback”, so that different intervention does not meet the stated requirement.

GNMI is a model-driven management interface commonly using gRPC streaming and structured path/value messages rather than a generic webpage. “Implement a supported gNMI client with secure gRPC connectivity and a valid Subscribe request for modeled paths” applies to that other condition. The reported evidence is a business integrates a regional network with public cloud using one dedicated physical circuit and assumes a separate routing VLAN on the same facility provides true disaster tolerance; this alternative would address the wrong dependency.

That change concerns qos class map matching order, where Traffic classification order and policy constructs can cause broad conditions to overshadow intended more-specific class handling. The reported issue instead stems from: Policy percentages alone do not preserve service if critical aggregate traffic exceeds reduced failover link capacity.

That change concerns qos per interface policy direction, where Input classification and policing operate on traffic entering an interface, while output scheduling applies to egress congestion. In this question the necessary remedy is “Create degraded-mode QoS and application admission policy based on backup capacity and essential services”, which this alternative does not provide.

That change concerns qos validation with actual queue counters, where A syntactically installed QoS policy does not establish that actual applications match intended classes or receive required forwarding treatment. The observed condition is a branch's primary WAN has 100 Mbps and backup cellular has 15 Mbps, but both use the same traffic allocation values with no degraded-mode plan; this mechanism addresses another problem.

That change concerns campus stp root placement, where Without deliberate STP root design, Layer 2 forwarding paths may traverse inappropriate access hardware. The reported issue instead stems from: Physical underlay IP connectivity does not by itself establish appropriate inter-fabric transit, route exchange and segmentation policy.

That change concerns sd access extended node role boundaries, where Extended nodes and ordinary fabric nodes have distinct supported roles and scale limits; uplink connection alone does not confer every fabric service. In this question the necessary remedy is “Design supported fabric-to-fabric transit via qualified borders and consistent virtual-network route and security policy”, which this alternative does not provide.

That change concerns sd access fabric capacity and failover, where Link redundancy within the fabric does not guarantee sufficient external border forwarding capacity during degraded operation. The observed condition is two independent SD-Access fabrics need policy-governed intersite reachability, but engineers connect only their individual IP underlays and expect overlay virtual networks to merge; this mechanism addresses another problem.

Link redundancy within the fabric does not guarantee sufficient external border forwarding capacity during degraded operation. “Size border nodes and redundant exits for N-minus-one load, applying failure-domain and traffic-engineering requirements” would remedy that alternative situation, but it would not correct the present issue: stateful inspection needs coherent bidirectional flow visibility, while independent routing cost choices can create asymmetric paths.

“Tie aggregate advertisement to required downstream reachability or redesign summarization and redundancy accordingly” is the supported response when a summary advertised by a border without valid components can attract and blackhole traffic during partial network failures. Here the decisive response is “Select a topology and route policy that maintain suitable symmetric inspected paths or supported state sharing”, so that different intervention does not meet the stated requirement.

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” applies to that other condition. The reported evidence is a campus distribution redesign installs a stateful firewall on one inter-building path while a lower-cost IGP return route bypasses that firewall; this alternative would address the wrong dependency.