Cisco 300-420 Bundle

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” 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.

“Design supported cloud on-ramp or cloud gateway integration with controlled routing, identity and service security policy” is the supported response when traditional centralized route topology can add delay and consume backbone capacity even when local cloud on-ramp options are available. 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.

TLS mutual authentication depends on valid identity and trust configuration, independent of basic network reachability. “Deploy approved certificates and trust anchors for the telemetry endpoint and collector, including correct service identity names” 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.

Logical network separation on one physical direct-connect facility does not eliminate common power, provider or meet-me-room failures. “Design redundant cloud interconnects with suitable facility diversity, BGP and controlled Internet or secondary private fallback” would remedy that alternative situation, but it would not correct the present issue: private transport does not automatically enforce tenant segmentation or prevent unintended route exchange into cloud environments.

“Implement a supported gNMI client with secure gRPC connectivity and a valid Subscribe request for modeled paths” is the supported response when GNMI is a model-driven management interface commonly using gRPC streaming and structured path/value messages rather than a generic webpage. Here the decisive response is “Integrate MPLS L3VPN with approved cloud private routing and select per-tenant VRF and gateway route policies”, so that different intervention does not meet the stated requirement.

TLS mutual authentication depends on valid identity and trust configuration, independent of basic network reachability. “Deploy approved certificates and trust anchors for the telemetry endpoint and collector, including correct service identity names” applies to that other condition. The reported evidence is a financial institution wants dedicated provider L3VPN connectivity to cloud private resources and proposes exporting every enterprise VRF into one common cloud virtual network; this alternative would address the wrong dependency.

That change concerns BGP route reflector cluster design, where Conventional iBGP full mesh grows quadratically and becomes costly to configure, observe and recover. The reported issue instead stems from: AS-path prepending mainly affects remote path selection; outbound path preference within the local AS is commonly controlled with local preference.

That change concerns BGP next hop self across ibgp, where iBGP typically preserves the external next hop, which must be reachable through the internal routing infrastructure. In this question the necessary remedy is “Set governed BGP local preference on inbound routes from the preferred provider, with consistent internal propagation”, which this alternative does not provide.

That change concerns BGP med neighboring exit choice, where Internal OSPF cost does not communicate an intended interconnect preference to the neighboring autonomous system. The observed condition is a dual-homed enterprise wants all internal sites to prefer the primary provider for outbound traffic but adjusts AS-path prepending on inbound advertisements instead; this mechanism addresses another problem.

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: shortcut VPN topology changes can bypass required inspection if the WAN policy assumes every flow transits a central hub.

“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 “Use a security-enforcing hub design or distributed inspection architecture with explicit policy for branch-to-branch traffic”, so that different intervention does not meet the stated requirement.

Multiple logical VLANs on the same physical CE and provider device do not provide independent failure domains. “Design separate CE devices, access paths and service-provider terminations in accordance with the required availability objective” applies to that other condition. The reported evidence is a company permits interbranch traffic only after central security inspection, but a newly deployed direct branch tunnel bypasses the hub firewall; this alternative would address the wrong dependency.

That change concerns syslog centralized security retention, where Local log storage and rollover cannot substitute for reliable centralized timestamped security event retention. The reported issue instead stems from: Without proper management traffic classification and minimum bandwidth, congestion can starve necessary operations traffic.

That change concerns snmpv3 authenticated management design, where Legacy community strings do not provide SNMPv3's user-based authentication and encryption capabilities needed by the policy. In this question the necessary remedy is “Classify authentic management flows and allocate controlled minimum service within the WAN's QoS policy”, which this alternative does not provide.

That change concerns out of band network management resiliency, where In-band-only management can share a fault with the network being repaired, eliminating the ability to recover remotely. The observed condition is a WAN runs at capacity during remote backup jobs and incident responders lose SSH and telemetry access precisely when troubleshooting is needed; this mechanism addresses another problem.

That change concerns dmvpn spoke to spoke optimization, where A purely hub-and-spoke forwarding policy can add latency and load when the DMVPN design is intended to allow direct spoke shortcuts. The reported issue instead stems from: GRE provides encapsulation for multiple protocols but does not itself encrypt or authenticate payload confidentiality.

That change concerns dmvpn nhrp registration reachability, where Dynamic spoke resolution needs correct NHRP network ID, authentication, hub mapping and reachable tunnel source rather than only a live Internet connection. In this question the necessary remedy is “Combine supported GRE transport with an appropriate IPsec protection design, or select a secure alternative meeting multicast needs”, which this alternative does not provide.

That change concerns sd wan edge last mile diversity, where Logical dual-circuit contracts may share a physical access path and suffer a common-cause outage. The observed condition is an architect proposes plain GRE between remote branches to carry multicast routing updates and claims GRE alone satisfies corporate confidentiality requirements; this mechanism addresses another problem.

That change concerns cisco sd wan management plane resilience, where Management availability and existing data-plane forwarding have different dependencies, while loss of manageability remains an operational risk. The reported issue instead stems from: Logical transport labels or TLOCs do not inherently represent independent circuits, carrier facilities or last-mile paths.

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. In this question the necessary remedy is “Map TLOCs to genuinely diverse approved transport interfaces and validate policy-based failover”, which this alternative does not provide.

That change concerns cisco sd wan omp control route design, where Data-plane tunnel presence does not guarantee that control-plane route advertisement and segmentation policy deliver needed service prefixes. The observed condition 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 mechanism addresses another problem.

MST region membership requires consistent region identifier, revision and VLAN mapping rather than matching only some VLAN names. “Align approved MST region configuration and verify boundary ports and per-instance root placement” would remedy that alternative situation, but it would not correct the present issue: a per-VLAN spanning-tree model scales protocol state with VLAN count and may become less efficient than suitable aggregated instances.

“Enable appropriate UDLD modes on supported fiber links and validate shutdown and recovery procedures” is the supported response when physical link-up is insufficient to guarantee bidirectional signal integrity, which can affect control-plane protocols and forwarding. Here the decisive response is “Assess MST or Layer 3 access boundaries against actual traffic steering and availability requirements”, so that different intervention does not meet the stated requirement.

Superior BPDUs on an untrusted downstream link can alter STP root selection unless the boundary is protected. “Enable Root Guard on appropriate downstream designated ports and keep intended root roles explicit” applies to that other condition. The reported evidence is a campus uses hundreds of VLANs with distinct rapid spanning-tree instances and experiences growing CPU and change-control complexity; this alternative would address the wrong dependency.

That change concerns sd access vxlan data plane role, where A fabric control plane supplies locator information, while the data plane uses supported VXLAN encapsulation to carry endpoint traffic. The reported issue instead stems from: Fabric overlay encapsulation adds overhead beyond ordinary IP reachability and depends on a healthy L3 underlay.

That change concerns sd access border node external integration, where Fabric overlay endpoints require a suitable border function to exchange external route reachability with nonfabric networks. In this question the necessary remedy is “Provide resilient IP underlay reachability and adequate end-to-end MTU for supported fabric encapsulation”, which this alternative does not provide.

That change concerns sd access lisp control plane mapping, where Fabric control-plane endpoint-to-location mapping must reflect movement and be consistent with current host registration. The observed condition is a new SD-Access fabric edge can reach control nodes by IP but VXLAN user traffic fails because the routed underlay path has insufficient MTU; this mechanism addresses another problem.

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” would remedy that alternative situation, but it would not correct the present issue: an IPv4-only underlay cannot natively carry IPv6 forwarding without an overlay or other transition capability.

“Enable and verify supported graceful restart with sensible stale timers and failover safeguards where appropriate” is the supported response when graceful restart depends on both peers' supported capabilities and bounded stale-route handling, not merely a routing session name. Here the decisive response is “Use a supported IPv6-over-IPv4 tunnel with correct endpoint reachability, encapsulation security and effective MTU”, so that different intervention does not meet the stated requirement.

BGP additional paths must satisfy supported multipath eligibility rules and configured maximum-path policy to share traffic. “Evaluate path attributes and supported multipath settings, then choose a design that preserves deterministic failover” applies to that other condition. The reported evidence 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 alternative would address the wrong dependency.

A per-VLAN spanning-tree model scales protocol state with VLAN count and may become less efficient than suitable aggregated instances. “Assess MST or Layer 3 access boundaries against actual traffic steering and availability requirements” would remedy that alternative situation, but it would not correct the present issue: a non-designated STP port losing expected control messages can create a loop if it incorrectly assumes the superior path vanished.

“Enable Root Guard on appropriate downstream designated ports and keep intended root roles explicit” is the supported response when superior BPDUs on an untrusted downstream link can alter STP root selection unless the boundary is protected. Here the decisive response is “Use Loop Guard on appropriate non-edge STP links and deploy complementary unidirectional link detection where supported”, so that different intervention does not meet the stated requirement.

Physical link-up is insufficient to guarantee bidirectional signal integrity, which can affect control-plane protocols and forwarding. “Enable appropriate UDLD modes on supported fiber links and validate shutdown and recovery procedures” applies to that other condition. The reported evidence is one of two redundant STP links stops receiving BPDUs due to a unidirectional fault but remains physically up, risking a blocked port transitioning to forwarding; this alternative would address the wrong dependency.