Cisco 300-420 Bundle

That change concerns eigrp feasible successor requirements, where An EIGRP feasible successor must satisfy its feasibility condition relative to the successor's feasible distance to prevent loops. The reported issue instead stems from: Unnecessary specific-route propagation increases state and change sensitivity without providing required central policy detail.

That change concerns eigrp authentication mismatched key chain, where Neighbor authentication parameters and permitted key windows must align or the routing protocol rejects peer messages. In this question the necessary remedy is “Apply well-bounded route summaries at distribution interfaces only after validating component networks and discard consequences”, which this alternative does not provide.

That change concerns eigrp unequal cost traffic sharing, where EIGRP unequal-cost load sharing is not enabled simply because multiple routes exist and is constrained by feasibility and variance. The observed condition is a distribution router advertises every tiny branch prefix separately into the EIGRP core even though branches are allocated in contiguous blocks; this mechanism addresses another problem.

That change concerns BGP multipath equal cost eligibility, where BGP additional paths must satisfy supported multipath eligibility rules and configured maximum-path policy to share traffic. The reported issue instead stems from: An IPv4-only underlay cannot natively carry IPv6 forwarding without an overlay or other transition capability.

That change concerns BGP community-based export policy, where Manual per-prefix policy misses newly onboarded routes when attributes and export rules are not centrally classified. In this question the necessary remedy is “Use a supported IPv6-over-IPv4 tunnel with correct endpoint reachability, encapsulation security and effective MTU”, which this alternative does not provide.

That change concerns BGP graceful restart state retention, where Graceful restart depends on both peers' supported capabilities and bounded stale-route handling, not merely a routing session name. The observed condition is a branch runs IPv6-only management endpoints over a provider transport that supports IPv4 underlay only, but the design expects native IPv6 routing to work end to end; this mechanism addresses another problem.

PIM sparse mode forwarding relies on supported multicast routing and receiver membership along the required multicast distribution tree. “Enable appropriate PIM and IGMP behavior on intended routed interfaces and validate RP and RPF reachability” would remedy that alternative situation, but it would not correct the present issue: without explicit multicast boundary control, group advertisements or forwarding may extend beyond authorized trust domains.

“Align multicast source reachability and acceptable RPF design with supported ECMP handling and stable upstream selection” is the supported response when multicast RPF decisions can be sensitive to unicast path selection, including ECMP and asymmetric routing behavior. Here the decisive response is “Apply supported multicast group or source boundary filtering at the appropriate WAN and tenant interfaces”, so that different intervention does not meet the stated requirement.

RP location affects shared-tree path efficiency and control resilience for ASM groups and can create a remote common-mode dependency. “Choose strategically located and redundant RPs considering source and receiver topology, routing cost and failover” applies to that other condition. The reported evidence is a company distributes executive multicast video to finance buildings, but the design allows the group to cross into an outsourced guest network; this alternative would address the wrong dependency.

A shared provider routing domain cannot preserve independent overlapping tenant address spaces and route targets without isolation. “Select a supported MPLS L3VPN design using separate VPN routing tables and approved route-target import/export policy” would remedy that alternative situation, but it would not correct the present issue: mobile backup is useful only if real coverage, policy, cost and failure independence support required branch services.

“Choose an eligible provider Layer 2 VPN or Ethernet private line design if extending a broadcast domain is genuinely required” is the supported response when an MPLS Layer 3 VPN routes IP among separated CE networks rather than delivering a transparent Layer 2 Ethernet service. Here the decisive response is “Design cellular failover with tested signal strength, provider diversity, data-plan capacity and selective critical traffic routing”, so that different intervention does not meet the stated requirement.

Ordinary port-level upgrades may not meet aggregate fiber-capacity and distance requirements when the optical transport must host many independent wavelengths. “Evaluate supported DWDM wavelengths, optics, optical budget, dispersion and protection channels for the transport design” applies to that other condition. The reported evidence 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 alternative would address the wrong dependency.

A totally stubby or regular stub area cannot originate external LSAs through an internal ASBR in the required manner. “Design a supported NSSA with correct Type 7 origination and ABR translation handling where needed” would remedy that alternative situation, but it would not correct the present issue: BGP additional paths must satisfy supported multipath eligibility rules and configured maximum-path policy to share traffic.

“Use a supported IPv6-over-IPv4 tunnel with correct endpoint reachability, encapsulation security and effective MTU” is the supported response when an IPv4-only underlay cannot natively carry IPv6 forwarding without an overlay or other transition capability. Here the decisive response is “Evaluate path attributes and supported multipath settings, then choose a design that preserves deterministic failover”, so that different intervention does not meet the stated requirement.

Manual per-prefix policy misses newly onboarded routes when attributes and export rules are not centrally classified. “Tag routes with an approved community scheme and enforce explicit export policy at each boundary” applies to that other condition. The reported evidence is an edge device has two BGP paths to the same prefix but operators expect load sharing merely because both routes appear in the neighbor table; this alternative would address the wrong dependency.

That change concerns sd access sgt micro segmentation, where IP-prefix ACLs become brittle when identity and endpoint groups move, while fabric policy can use scalable group-based classification. The reported issue instead stems from: Fabric wireless requires supported controller and edge integration and consistent segmentation assignments for mobile clients.

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. In this question the necessary remedy is “Design the supported fabric wireless control-plane and data-plane integration with validated WLAN-to-VN mapping”, which this alternative does not provide.

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. The observed condition is wireless clients roam between access points attached to a fabric, but engineers have not designed how controllers integrate with fabric edge nodes and virtual networks; this mechanism addresses another problem.

Average throughput can hide instantaneous bursts and delay variation that disrupt real-time media even when link utilization seems moderate. “Reserve suitable queue and burst tolerance based on codec behavior, media priority and empirically observed peak load” would remedy that alternative situation, but it would not correct the present issue: policy percentages alone do not preserve service if critical aggregate traffic exceeds reduced failover link capacity.

“Refine class-map criteria and supported policy evaluation to classify the real-time flows before generic groups” is the supported response when traffic classification order and policy constructs can cause broad conditions to overshadow intended more-specific class handling. Here the decisive response is “Create degraded-mode QoS and application admission policy based on backup capacity and essential services”, so that different intervention does not meet the stated requirement.

Input classification and policing operate on traffic entering an interface, while output scheduling applies to egress congestion. “Place supported ingress policing and remarking at appropriate boundaries and egress queuing at the actual bottleneck” applies to that other condition. The reported evidence 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 alternative would address the wrong dependency.

That change concerns cisco sd wan management and data path separation, where Using only the affected data-plane overlay for operational access can eliminate remote troubleshooting when the fabric fails. The reported issue instead stems from: Bandwidth alone does not determine application suitability when propagation delay and jitter exceed interactive service limits.

That change concerns hybrid wan internet mpls policy separation, where A hybrid WAN needs explicit route and security decisions because reachability alone does not guarantee sensitive traffic uses approved paths. In this question the necessary remedy is “Choose appropriate low-latency WAN transport and QoS treatment, evaluating cost, resilience and route diversity”, which this alternative does not provide.

That change concerns wan circuit oversubscription under failover, where N-minus-one operation cannot carry combined load if each remaining link lacks spare capacity or business traffic prioritization. The observed condition 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 mechanism addresses another problem.

Without deliberate STP root design, Layer 2 forwarding paths may traverse inappropriate access hardware. “Include root placement and protection checks in switch onboarding templates” would remedy that alternative situation, but it would not correct the present issue: unfiltered inter-VRF route leaking can undermine segmentation even if each tenant has its own routing instance.

“Test partial reachability failures, not only complete router outages, when validating multicampus route policy” 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 “Audit shared services route leaks and ACLs together after each tenant or service onboarding”, so that different intervention does not meet the stated requirement.

Stateful inspection needs coherent bidirectional flow visibility, while independent routing cost choices can create asymmetric paths. “Include reverse-path verification in campus security zone design and ECMP changes” applies to that other condition. The reported evidence is a guest campus VRF is permitted to reach a shared DNS service but a broad route leak accidentally exposes internal management subnets; this alternative would address the wrong dependency.

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” 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.

PIM DR election provides a defined designated router role on a multiaccess segment to avoid conflicting join responsibilities. “Design suitable PIM interface priorities and neighbor reachability for predictable designated-router selection” 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.

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.