Cisco 300-420 Bundle

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.

Missing site-level address summarization increases routing state and exposes the WAN to local campus topology churn. “Plan contiguous campus address blocks and advertise valid site summaries at L3 distribution or WAN boundaries” would remedy that alternative situation, but it would not correct the present issue: extending Layer 2 broadly across campus buildings increases loop, convergence and failure-domain exposure.

“Apply explicit redistribution filters, tags, metrics and domain ownership at each boundary with deliberate failure fallback” is the supported response when bidirectional multipoint redistribution without route tagging or authoritative direction can reintroduce routes into their source protocol. Here the decisive response is “Design routed access where supported, using local Layer 3 boundaries and deterministic IGP connectivity between buildings”, so that different intervention does not meet the stated requirement.

An SVI routed ACL does not necessarily inspect intra-VLAN switched frames that never reach Layer 3 forwarding. “Design supported VACL, private VLAN or separate VLAN segmentation according to local traffic patterns and platform capabilities” applies to that other condition. The reported evidence is a multicampus organization extends each access VLAN over multiple buildings to preserve gateway placement, creating a large shared spanning-tree fault domain; this alternative would address the wrong dependency.

A single endpoint map/control-plane service is a common-mode availability risk even with redundant data-plane links. “Design supported control-plane node redundancy and test endpoint registration continuity during node loss” would remedy that alternative situation, but it would not correct the present issue: IP-prefix ACLs become brittle when identity and endpoint groups move, while fabric policy can use scalable group-based classification.

“Select a supported SD-Access multicast forwarding model and test receivers across fabric edges and virtual networks” is the supported response when fabric overlay multicast support and replication design have specific control and data-plane requirements beyond simple underlay multicast reachability. Here the decisive response is “Use authorized scalable group tags and matching group-based access policy integrated with the intended identity service”, so that different intervention does not meet the stated requirement.

Security group policy alone may not replace full virtual-network level route isolation where separate macrosegments are required. “Design distinct fabric virtual networks with appropriate external borders and tightly defined shared services” applies to that other condition. The reported evidence is two employee groups must share a fabric virtual network for common application routing but security wants group-based access without maintaining thousands of individual IPv4 ACL entries; this alternative would address the wrong dependency.

Mixed or unsuitable metric styles can undermine consistent path-cost planning and overflow the intended metric range. “Standardize supported wide-metric design and audit interface cost policies across participating IS-IS devices” 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.

“Coordinate supported EIGRP authentication changes and key rollover across both peers with safe cutover” is the supported response when neighbor authentication parameters and permitted key windows must align or the routing protocol rejects peer messages. Here the decisive response is “Use explicit tag-based redistribution policy, defined metrics and directional filters at well-documented borders”, so that different intervention does not meet the stated requirement.

Unnecessary specific-route propagation increases state and change sensitivity without providing required central policy detail. “Apply well-bounded route summaries at distribution interfaces only after validating component networks and discard consequences” 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 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 reported issue instead stems from: Encryption hides much application payload from intermediate classifiers, so deep packet inspection may not see per-app content inside the tunnel.

That change concerns call admission and voice capacity, where Priority queuing alone cannot create bandwidth beyond circuit capacity, and too many concurrent sessions can oversubscribe voice allocation. In this question the necessary remedy is “Classify and mark before encryption or use supported trusted tunnel metadata and policy-based identification at appropriate endpoints”, which this alternative does not provide.

That change concerns qos remarking across carrier boundary, where DSCP semantics and provider class-of-service mappings are not necessarily preserved across an independent administrative domain. The observed condition is an organization classifies applications by payload signatures inside IPsec tunnels and then finds all encrypted business traffic mapped to a single generic class; this mechanism addresses another problem.

That change concerns mpls direct cloud provider integration, where Private transport does not automatically enforce tenant segmentation or prevent unintended route exchange into cloud environments. The reported issue instead stems from: RESTCONF uses resource-oriented HTTP methods with defined read and write semantics, so GET is not an appropriate configuration write operation.

That change concerns netconf versus restconf transport selection, where NETCONF and RESTCONF share model-driven concepts but use different protocol transports, operation semantics and session behavior. In this question the necessary remedy is “Use supported RESTCONF PATCH, PUT or POST methods at correct YANG resource paths with authorization and content types”, which this alternative does not provide.

That change concerns on change telemetry event notifications, where Coarse periodic publication can delay visibility of short state transitions and is not equivalent to supported event-driven on-change reporting. The observed condition is an automation tool sends a GET request to change a router interface description and assumes any successful HTTP response implies a configuration mutation; this mechanism addresses another problem.

An oversized or unbounded strict-priority queue can consume interface capacity and deny adequate service to other classes. “Reserve low-latency priority treatment for justified real-time traffic with controlled bandwidth and balanced class allocations” would remedy that alternative situation, but it would not correct the present issue: uncoordinated system clocks undermine log chronology, audit correlation and incident reconstruction.

“Design appropriate collector and transport redundancy with supported failover and secure retention behavior” is the supported response when central monitoring infrastructure can become a single point of failure even when individual access devices have redundant uplinks. Here the decisive response is “Use resilient approved NTP sources with authenticated or trusted network delivery where supported”, so that different intervention does not meet the stated requirement.

ASM shared-tree setup may depend on reachable RP control functions that need deliberate redundancy. “Design supported redundant RP mechanisms with consistent group mappings and reachability across the multicast domain” applies to that other condition. The reported evidence is two distribution devices report the same routing flap five minutes apart because one device uses an unsynchronized clock; this alternative would address the wrong dependency.

IP-prefix ACLs become brittle when identity and endpoint groups move, while fabric policy can use scalable group-based classification. “Audit SGT classification and policy matrix changes when onboarding new job roles” would remedy that alternative situation, but it would not correct the present issue: security group policy alone may not replace full virtual-network level route isolation where separate macrosegments are required.

“Model controller and node availability separately from physical fabric underlay paths” is the supported response when a single endpoint map/control-plane service is a common-mode availability risk even with redundant data-plane links. Here the decisive response is “Use virtual-network boundaries for real routing isolation and review any exception-based cross-VN reachability”, so that different intervention does not meet the stated requirement.

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” applies to that other condition. The reported evidence is a finance and guest population share the same fabric virtual network even though compliance requires independent routing tables and external access paths; this alternative would address the wrong dependency.

Ordinary underlay reachability does not assign endpoint onboarding and VXLAN edge functions to a nonfabric access device. “Provision eligible access devices as supported fabric edge nodes and verify host onboarding and virtual network assignments” would remedy that alternative situation, but it would not correct the present issue: high session counts and excessively aggressive timers can exhaust control resources and cause false routing flaps.

“Select a topology and route policy that maintain suitable symmetric inspected paths or supported state sharing” is the supported response when stateful inspection needs coherent bidirectional flow visibility, while independent routing cost choices can create asymmetric paths. Here the decisive response is “Model required convergence classes and scale BFD deployment selectively on critical routed interfaces”, so that different intervention does not meet the stated requirement.

A summary advertised by a border without valid components can attract and blackhole traffic during partial network failures. “Tie aggregate advertisement to required downstream reachability or redesign summarization and redundancy accordingly” applies to that other condition. The reported evidence is a design mandates subsecond link failure reaction on hundreds of campus peers and enables aggressive BFD for every adjacency without capacity estimation; this alternative would address the wrong dependency.

A fabric control plane supplies locator information, while the data plane uses supported VXLAN encapsulation to carry endpoint traffic. “Separate control-plane mapping checks from data-plane tunnel validation in incident runbooks” would remedy that alternative situation, but it would not correct the present issue: fabric overlay encapsulation adds overhead beyond ordinary IP reachability and depends on a healthy L3 underlay.

“Monitor control-plane registration freshness and duplicate endpoint identities in multibuilding fabrics” is the supported response when fabric control-plane endpoint-to-location mapping must reflect movement and be consistent with current host registration. Here the decisive response is “Test fabric data-plane MTU and underlay reachability as separate acceptance criteria”, so that different intervention does not meet the stated requirement.

Fabric overlay endpoints require a suitable border function to exchange external route reachability with nonfabric networks. “Evaluate border redundancy, route advertisement scope and external underlay handoff before deployment” applies to that other condition. The reported evidence 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 alternative would address the wrong dependency.

That change concerns gre tunnel mtu and fragmentation, where Encapsulation and encryption overhead reduce effective path MTU, and missing PMTUD control messages can stall large packets. The reported issue instead stems from: Ordinary port-level upgrades may not meet aggregate fiber-capacity and distance requirements when the optical transport must host many independent wavelengths.

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. In this question the necessary remedy is “Evaluate supported DWDM wavelengths, optics, optical budget, dispersion and protection channels for the transport design”, which this alternative does not provide.

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. The observed condition is two data centers need many high-throughput channels over existing dark fiber but an architect proposes a single low-rate Ethernet handoff for each future application; this mechanism addresses another problem.