Cisco 300-420 Bundle

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 reported issue instead stems from: Neighbor authentication parameters and permitted key windows must align or the routing protocol rejects peer messages.

That change concerns eigrp route summarization at hub, where Unnecessary specific-route propagation increases state and change sensitivity without providing required central policy detail. In this question the necessary remedy is “Coordinate supported EIGRP authentication changes and key rollover across both peers with safe cutover”, which this alternative does not provide.

That change concerns eigrp hub topology route leaking, where Uncontrolled bidirectional redistribution can reintroduce routes, create loops and lose source-of-truth route preference. The observed condition is two enterprise EIGRP neighbors cease exchanging routes after only one endpoint changes key identifiers during security hardening; this mechanism addresses another problem.

Unrestricted BGP export policy exposes destinations not authorized for upstream announcement and risks routing leaks. “Perform automated prefix allowlist tests and route-leak simulations before modifying BGP transit peers” would remedy that alternative situation, but it would not correct the present issue: EIGRP unequal-cost load sharing is not enabled simply because multiple routes exist and is constrained by feasibility and variance.

“Require prefix allocation consistency before EIGRP summarization is enabled in production” is the supported response when unnecessary specific-route propagation increases state and change sensitivity without providing required central policy detail. Here the decisive response is “Review maximum path and variance behavior during circuit upgrades and dual-WAN commissioning”, so that different intervention does not meet the stated requirement.

Uncontrolled bidirectional redistribution can reintroduce routes, create loops and lose source-of-truth route preference. “Audit redistribution route tags and policy match order whenever a new domain boundary is added” applies to that other condition. The reported evidence is a regional hub has a primary 100 Mbps path and secondary 50 Mbps path and wants controlled EIGRP unequal-cost use, but the default setting installs only equal-cost routes; this alternative would address the wrong dependency.

That change concerns rpf multicast source route check, where Multicast RPF typically checks the route back toward the source or RP, not merely whether a receiver destination is reachable. The reported issue instead stems from: Central monitoring infrastructure can become a single point of failure even when individual access devices have redundant uplinks.

That change concerns pim sparse mode rendezvous point resilience, where ASM shared-tree setup may depend on reachable RP control functions that need deliberate redundancy. In this question the necessary remedy is “Design appropriate collector and transport redundancy with supported failover and secure retention behavior”, which this alternative does not provide.

That change concerns ntp time quality in network operations, where Uncoordinated system clocks undermine log chronology, audit correlation and incident reconstruction. The observed condition is a national enterprise sends every configuration backup and log to one management collector in a single data center with no alternate destination; this mechanism addresses another problem.

Multicast RPF decisions can be sensitive to unicast path selection, including ECMP and asymmetric routing behavior. “Align multicast source reachability and acceptable RPF design with supported ECMP handling and stable upstream selection” would remedy that alternative situation, but it would not correct the present issue: random early detection is usually better aligned with responsive TCP queues than with high-priority delay-sensitive voice traffic.

“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 “Use appropriate congestion avoidance on suitable best-effort TCP classes and protect voice through controlled priority service”, so that different intervention does not meet the stated requirement.

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” applies to that other condition. The reported evidence is a network team enables WRED on the expedited voice queue and expects random early drops to improve low-latency real-time delivery; this alternative would address the wrong dependency.

An MPLS Layer 3 VPN routes IP among separated CE networks rather than delivering a transparent Layer 2 Ethernet service. “Assess broadcast extension failure domains before buying a transparent transport solely to avoid route design” would remedy that alternative situation, but it would not correct the present issue: n-minus-one operation cannot carry combined load if each remaining link lacks spare capacity or business traffic prioritization.

“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 “Report both normal and degraded capacity forecasts when approving enterprise WAN budgets”, so that different intervention does not meet the stated requirement.

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” applies to that other condition. The reported evidence is two regional WAN links each run at eighty percent peak utilization, but design documents promise full service during loss of either one; this alternative would address the wrong dependency.

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” would remedy that alternative situation, but it would not correct the present issue: physical underlay IP connectivity does not by itself establish appropriate inter-fabric transit, route exchange and segmentation policy.

“Test roaming, controller failover and policy consistency before broad fabric wireless expansion” is the supported response when fabric wireless requires supported controller and edge integration and consistent segmentation assignments for mobile clients. Here the decisive response is “Review transit scalability, border redundancy and trust-boundary translation at every inter-fabric connection”, so that different intervention does not meet the stated requirement.

Link redundancy within the fabric does not guarantee sufficient external border forwarding capacity during degraded operation. “Use measured peak traffic and failure-mode utilization when capacity planning SD-Access borders” applies to that other condition. The reported evidence 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 alternative would address the wrong dependency.

Multihoming and address translation must account for both directions; outbound route changes alone may not preserve return paths. “Design consistent BGP advertisement, NAT and routing failover so return flows follow the reachable secondary path” would remedy that alternative situation, but it would not correct the present issue: naive unicast replication can consume excessive WAN capacity, while multicast support depends on platform and overlay design.

“Use separate service VPN or VRF contexts with explicit leak rules and security policy at authorized shared-service borders” is the supported response when an unsegmented overlay routing context can make trust-boundary errors more likely even if some edge access rules exist. Here the decisive response is “Choose a supported multicast distribution and replication approach with measured receiver count and transport constraints”, so that different intervention does not meet the stated requirement.

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” applies to that other condition. The reported evidence is a corporate town hall multicast stream must reach dozens of remote branches, but the design duplicates full-rate unicast copies at every WAN hop; this alternative would address the wrong dependency.

An MPLS Layer 3 VPN routes IP among separated CE networks rather than delivering a transparent Layer 2 Ethernet service. “Choose an eligible provider Layer 2 VPN or Ethernet private line design if extending a broadcast domain is genuinely required” would remedy that alternative situation, but it would not correct the present issue: a shared provider routing domain cannot preserve independent overlapping tenant address spaces and route targets without isolation.

“Evaluate supported DWDM wavelengths, optics, optical budget, dispersion and protection channels for the transport design” is the supported response when ordinary port-level upgrades may not meet aggregate fiber-capacity and distance requirements when the optical transport must host many independent wavelengths. Here the decisive response is “Select a supported MPLS L3VPN design using separate VPN routing tables and approved route-target import/export policy”, so that different intervention does not meet the stated requirement.

Multipoint Ethernet services and many independent E-Line circuits have different Layer 2 forwarding and spanning-tree implications. “Choose appropriate Metro Ethernet point-to-point or multipoint service topology with explicit VLAN and loop-avoidance design” applies to that other condition. The reported evidence is an enterprise has many branch customers with overlapping private prefixes and proposes one shared provider IP routing instance for all tenants; 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: priority queuing alone cannot create bandwidth beyond circuit capacity, and too many concurrent sessions can oversubscribe voice allocation.

“Implement appropriate CBWFQ or platform-supported scheduler weights after classifying actual traffic” is the supported response when without class-based queue service, different traffic priorities may compete equally under congestion rather than receiving guaranteed minimum allocations. Here the decisive response is “Design call admission or session limits based on codec overhead and failover bandwidth, with controlled class policies”, so that different intervention does not meet the stated requirement.

Encryption hides much application payload from intermediate classifiers, so deep packet inspection may not see per-app content inside the tunnel. “Classify and mark before encryption or use supported trusted tunnel metadata and policy-based identification at appropriate endpoints” applies to that other condition. The reported evidence is a small branch has a 3 Mbps WAN with no admission control and permits twenty simultaneous high-bitrate voice sessions, causing severe jitter; this alternative would address the wrong dependency.

A hybrid deployment can transfer sensitive data or metadata across administrative and geographic boundaries even when application compute stays on-premises. “Design controlled hybrid data flow, regional placement and access policies that satisfy residency and connectivity requirements” would remedy that alternative situation, but it would not correct the present issue: GNMI is a model-driven management interface commonly using gRPC streaming and structured path/value messages rather than a generic webpage.

“Deploy approved certificates and trust anchors for the telemetry endpoint and collector, including correct service identity names” is the supported response when TLS mutual authentication depends on valid identity and trust configuration, independent of basic network reachability. Here the decisive response is “Implement a supported gNMI client with secure gRPC connectivity and a valid Subscribe request for modeled paths”, so that different intervention does not meet the stated requirement.

Private transport does not automatically enforce tenant segmentation or prevent unintended route exchange into cloud environments. “Integrate MPLS L3VPN with approved cloud private routing and select per-tenant VRF and gateway route policies” applies to that other condition. The reported evidence is a collector opens an HTTP webpage and expects to receive streaming gNMI telemetry messages as ordinary JSON page content; this alternative would address the wrong dependency.

Security group policy alone may not replace full virtual-network level route isolation where separate macrosegments are required. “Use virtual-network boundaries for real routing isolation and review any exception-based cross-VN reachability” would remedy that alternative situation, but it would not correct the present issue: a common routing instance cannot enforce independent overlapping IP destinations and controlled route exposure by itself.

“Test actual Layer 2 forwarding paths before certifying an SVI-only rule as local east-west isolation” is the supported response when an SVI routed ACL does not necessarily inspect intra-VLAN switched frames that never reach Layer 3 forwarding. Here the decisive response is “Require security approval and route-leak testing for every campus shared-services exception”, so that different intervention does not meet the stated requirement.

Extending Layer 2 broadly across campus buildings increases loop, convergence and failure-domain exposure. “Set explicit maximum Layer 2 failure domains during new-building network approvals” applies to that other condition. The reported evidence is guest kiosks and regulated finance terminals share one campus routing table despite requirements that their overlapping address blocks remain isolated; this alternative would address the wrong dependency.