Cisco 300-420 Bundle

Conventional iBGP full mesh grows quadratically and becomes costly to configure, observe and recover. “Introduce redundant route reflectors with appropriate client hierarchy and loop-prevention identifiers” would remedy that alternative situation, but it would not correct the present issue: AS-path prepending mainly affects remote path selection; outbound path preference within the local AS is commonly controlled with local preference.

“Use supported BGP MED where appropriate, coordinate the provider's comparison behavior and keep resilient alternate exits” is the supported response when internal OSPF cost does not communicate an intended interconnect preference to the neighboring autonomous system. Here the decisive response is “Set governed BGP local preference on inbound routes from the preferred provider, with consistent internal propagation”, so that different intervention does not meet the stated requirement.

IBGP typically preserves the external next hop, which must be reachable through the internal routing infrastructure. “Provide appropriate next-hop-self policy or valid internal reachability for external BGP next hops with loop-free forwarding” applies to that other condition. The reported evidence 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 alternative would address the wrong dependency.

A dense many-to-many application can impose excessive source tree state if its delivery model ignores suitable shared bidirectional multicast designs. “Evaluate bidirectional PIM or another supported distribution method against source count, RP and security requirements” would remedy that alternative situation, but it would not correct the present issue: ASM initially uses a shared RP tree and may switch to source-specific shortest-path forwarding according to design and platform behavior.

“Design suitable PIM interface priorities and neighbor reachability for predictable designated-router selection” is the supported response when PIM DR election provides a defined designated router role on a multiaccess segment to avoid conflicting join responsibilities. Here the decisive response is “Evaluate supported SPT threshold and source-tree design for bandwidth and latency goals without creating RPF inconsistencies”, so that different intervention does not meet the stated requirement.

Source-specific multicast applications need supported source-aware receiver membership signaling, commonly IGMPv3 for IPv4. “Design SSM-compatible group range, sender addressing and receiver IGMPv3 support end to end” applies to that other condition. The reported evidence is a PIM sparse-mode ASM network sends high-rate streaming traffic through the rendezvous point even after receivers could reach a more efficient source tree; this alternative would address the wrong dependency.

An SVI routed ACL does not necessarily inspect intra-VLAN switched frames that never reach Layer 3 forwarding. “Test actual Layer 2 forwarding paths before certifying an SVI-only rule as local east-west isolation” would remedy that alternative situation, but it would not correct the present issue: missing site-level address summarization increases routing state and exposes the WAN to local campus topology churn.

“Set explicit maximum Layer 2 failure domains during new-building network approvals” is the supported response when extending Layer 2 broadly across campus buildings increases loop, convergence and failure-domain exposure. Here the decisive response is “Coordinate IPAM, summarization and discard behavior before opening new campus subnet ranges”, so that different intervention does not meet the stated requirement.

Bidirectional multipoint redistribution without route tagging or authoritative direction can reintroduce routes into their source protocol. “Validate tags and filtering under loss of either redistribution border router” applies to that other condition. The reported evidence is three campus sites advertise hundreds of access prefixes into a common WAN but changes at one site continuously trigger WAN routing state updates; 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: random early detection is usually better aligned with responsive TCP queues than with high-priority delay-sensitive voice traffic.

“Negotiate and implement DSCP-to-provider-CoS mapping and verify marking at each trust boundary” is the supported response when DSCP semantics and provider class-of-service mappings are not necessarily preserved across an independent administrative domain. 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.

Priority queuing alone cannot create bandwidth beyond circuit capacity, and too many concurrent sessions can oversubscribe voice allocation. “Design call admission or session limits based on codec overhead and failover bandwidth, with controlled class policies” 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.

That change concerns openconfig cross-platform telemetry models, where OpenConfig provides vendor-neutral model definitions whose implemented paths and capabilities must still be validated per platform. The reported issue instead stems from: NETCONF can expose candidate datastores, locking and commit operations where supported, unlike assuming every management interface has equivalent transactions.

That change concerns YANG schema revision and path versioning, where Machine-readable data model revisions and capabilities can differ across platform versions even if management connectivity remains healthy. In this question the necessary remedy is “Design a supported NETCONF workflow with lock, edit-config, validate, commit and rollback handling for the device capabilities”, which this alternative does not provide.

That change concerns ietf versus vendor YANG model portability, where Vendor-native data models may expose platform-specific schema that cannot be queried identically across different vendors. The observed condition is a network orchestrator must stage and validate multiple changes before activation but uses isolated individual REST calls with no candidate configuration review; this mechanism addresses another problem.

An EIGRP feasible successor must satisfy its feasibility condition relative to the successor's feasible distance to prevent loops. “Include EIGRP feasibility checks in redundancy acceptance instead of judging backups from raw bandwidth alone” would remedy that alternative situation, but it would not correct the present issue: uncontrolled bidirectional redistribution can reintroduce routes, create loops and lose source-of-truth route preference.

“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 “Audit redistribution route tags and policy match order whenever a new domain boundary is added”, so that different intervention does not meet the stated requirement.

EIGRP unequal-cost load sharing is not enabled simply because multiple routes exist and is constrained by feasibility and variance. “Review maximum path and variance behavior during circuit upgrades and dual-WAN commissioning” applies to that other condition. The reported evidence is two autonomous branch EIGRP routing domains redistribute into one core and begin sending learned routes back into the origin domain; this alternative would address the wrong dependency.

That change concerns wake on lan broadcast boundary, where Ordinary directed and local broadcasts do not automatically cross routed boundaries, so an explicit authorized delivery design is required. The reported issue instead stems from: Available PoE power budget and per-port capabilities determine whether simultaneous endpoint power requirements can be met.

That change concerns multichassis link peer failure, where A conventional port channel cannot span unrelated independent switches without a supported multichassis or stacking mechanism. In this question the necessary remedy is “Calculate endpoint power demand, switch capacity and redundancy margins and choose appropriate power supplies or models”, which this alternative does not provide.

That change concerns campus port security mac limit, where Without port security or identity-aware access control, a simple access port may learn multiple endpoint MAC addresses without limitation. The observed condition is a network redesign adds video endpoints to every access port but budgets only for switch port count, ignoring PoE class and aggregate power draw; this mechanism addresses another problem.

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: openConfig provides vendor-neutral model definitions whose implemented paths and capabilities must still be validated per platform.

“Prefer a suitable standards-based IETF model for portable interface telemetry, documenting implementation gaps and vendor extensions” is the supported response when vendor-native data models may expose platform-specific schema that cannot be queried identically across different vendors. Here the decisive response is “Select supported OpenConfig telemetry modules, verify revisions and normalize exceptions without assuming universal coverage”, so that different intervention does not meet the stated requirement.

Standardized models do not necessarily represent every vendor-specific operational or configuration feature. “Use the supported Cisco native YANG model for the particular feature with platform and software-version capability checks” applies to that other condition. The reported evidence is a monitoring platform wants consistent operational telemetry across diverse vendor routers, but teams conflate OpenConfig definitions with the device's vendor-specific CLI configuration; this alternative would address the wrong dependency.

In-band-only management can share a fault with the network being repaired, eliminating the ability to recover remotely. “Provide secure out-of-band management through independent transport, power and authentication suitable for critical nodes” would remedy that alternative situation, but it would not correct the present issue: legacy community strings do not provide SNMPv3's user-based authentication and encryption capabilities needed by the policy.

“Classify authentic management flows and allocate controlled minimum service within the WAN's QoS policy” is the supported response when without proper management traffic classification and minimum bandwidth, congestion can starve necessary operations traffic. Here the decisive response is “Design supported SNMPv3 users, auth/privacy mechanisms, least-privilege views and central credential lifecycle”, so that different intervention does not meet the stated requirement.

Local log storage and rollover cannot substitute for reliable centralized timestamped security event retention. “Design redundant remote syslog collectors with protected transport, appropriate facilities and retention controls” applies to that other condition. The reported evidence is a large enterprise collects SNMP interface counters using a shared SNMPv2 community across all regions and must meet per-user authentication and privacy controls; this alternative would address the wrong dependency.

Without port security or identity-aware access control, a simple access port may learn multiple endpoint MAC addresses without limitation. “Deploy suitable port security or 802.1X/MAB policies with sensible violation and recovery handling for endpoint types” would remedy that alternative situation, but it would not correct the present issue: physical link-up is insufficient to guarantee bidirectional signal integrity, which can affect control-plane protocols and forwarding.

“Align approved MST region configuration and verify boundary ports and per-instance root placement” is the supported response when MST region membership requires consistent region identifier, revision and VLAN mapping rather than matching only some VLAN names. Here the decisive response is “Enable appropriate UDLD modes on supported fiber links and validate shutdown and recovery procedures”, so that different intervention does not meet the stated requirement.

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” applies to that other condition. The reported evidence is a duplex fiber campus uplink works in one direction but not the other, and interface carrier stays partially healthy while protocols behave unpredictably; this alternative would address the wrong dependency.

That change concerns BGP prefix filter outbound boundary, where Unrestricted BGP export policy exposes destinations not authorized for upstream announcement and risks routing leaks. The reported issue instead stems from: Layer 1 carrier state may not reveal a downstream path failure and slow neighbor detection extends blackhole time.

That change concerns ospf route authentication consistency, where Unauthenticated routing adjacencies on a shared segment create topology-manipulation exposure and accidental peer acceptance. In this question the necessary remedy is “Deploy supported BFD for the intended OSPF peers, validate timers against platform capacity and test false-positive risk”, which this alternative does not provide.

That change concerns BGP address families for ipv6 peers, where A BGP TCP session does not automatically negotiate or advertise every address family without appropriate capabilities and policy. The observed condition is an OSPF transport remains physically up during a middle-network failure and the route takes too long to reconverge using default Hello and dead timers; this mechanism addresses another problem.