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This option proposes: Inspect traffic classifier matches, policy routing next-hop eligibility, egress statistics and the normal destination route that would otherwise apply. It addresses the different topic Policy-based routing versus destination routing, not the directly tested VRRP interface tracking and controlled preemption failure in the stated incident (An operator enables immediate preemption after a flapping upstream circuit and sees gateway ownership oscillate repeatedly with each short restoration.).

This option proposes: Inspect local and remote BFD configured minima, actual negotiated intervals, multiplier values, CPU pressure and observed detection timestamps. It addresses the different topic BFD detection multiplier and negotiated timers, not the directly tested VRRP interface tracking and controlled preemption failure in the stated incident (An operator enables immediate preemption after a flapping upstream circuit and sees gateway ownership oscillate repeatedly with each short restoration.).

This option proposes: Compare host ARP for the virtual gateway, advertised VRRP virtual MAC, switch forwarding table, master state and test traffic during takeover. It addresses the different topic VRRP virtual MAC and endpoint ARP continuity, not the directly tested VRRP interface tracking and controlled preemption failure in the stated incident (An operator enables immediate preemption after a flapping upstream circuit and sees gateway ownership oscillate repeatedly with each short restoration.).

That option concerns IS-IS LSP synchronization using CSNP and PSNP. That follows from the targeted Recommended action: Configure VRRP priority tracking with suitable preemption behavior so loss of upstream connectivity changes the preferred gateway.

This option proposes: The intended higher-priority eligible router answers for the shared gateway while the backup remains prepared for a takeover. It addresses the different topic VRRP master election priority and tie breaks, not the directly tested VRRP interface tracking and controlled preemption failure in the stated incident (An operator enables immediate preemption after a flapping upstream circuit and sees gateway ownership oscillate repeatedly with each short restoration.).

That option concerns BFD detection multiplier and negotiated timers. That follows from the targeted Recommended action: Configure VRRP priority tracking with suitable preemption behavior so loss of upstream connectivity changes the preferred gateway.

This option proposes: Assume a configured BFD transmit interval alone exactly equals the detection timeout regardless of the peer's receive requirement or detection multiplier. It addresses the different topic BFD detection multiplier and negotiated timers, not the directly tested VRRP interface tracking and controlled preemption failure in the stated incident (An operator enables immediate preemption after a flapping upstream circuit and sees gateway ownership oscillate repeatedly with each short restoration.).

This option proposes: Expect an EVPN Type 2 MAC advertisement alone to make an unreachable underlay VTEP routable without any transport path. It addresses the different topic MP-BGP EVPN route types and forwarding separation, not the directly tested VRRP interface tracking and controlled preemption failure in the stated incident (An operator enables immediate preemption after a flapping upstream circuit and sees gateway ownership oscillate repeatedly with each short restoration.).

This option proposes: Assume two routers can each configure a different virtual IP for the same VRRP group and still present one consistent default gateway to hosts. It addresses the different topic VRRP master election priority and tie breaks, not the directly tested VRRP interface tracking and controlled preemption failure in the stated incident (An operator enables immediate preemption after a flapping upstream circuit and sees gateway ownership oscillate repeatedly with each short restoration.).

This option proposes: Analyze Virtual Router Redundancy Protocol master election using priorities and the virtual router ID instead of a router's physical interface address alone. It addresses the different topic VRRP master election priority and tie breaks, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (An employee's workstation keeps sending to the configured virtual IPv4 gateway after the master fails and network staff think the IP must be changed manually.).

This option proposes: Calculate or verify the practical failure-detection threshold from BFD transmit intervals, advertised receive intervals and the detect multiplier. It addresses the different topic BFD detection multiplier and negotiated timers, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (An employee's workstation keeps sending to the configured virtual IPv4 gateway after the master fails and network staff think the IP must be changed manually.).

This option proposes: Troubleshoot BGP establishment by distinguishing TCP port 179 transport, peer configuration and OPEN capability negotiation. It addresses the different topic BGP transport reachability and session states, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (An employee's workstation keeps sending to the configured virtual IPv4 gateway after the master fails and network staff think the IP must be changed manually.).

This option proposes: AAA separates authentication, authorization and accounting for device management, while SSH protects management sessions and access policies can limit trusted administrative sources. It addresses the different topic Network device AAA role SSH and management-plane protection, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (An employee's workstation keeps sending to the configured virtual IPv4 gateway after the master fails and network staff think the IP must be changed manually.).

This option proposes: VRRP tracking can reduce a router's effective priority when a monitored interface or related condition fails; preemption and delay choices determine whether an eligible higher-priority backup takes over as intended. It addresses the different topic VRRP interface tracking and controlled preemption, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (An employee's workstation keeps sending to the configured virtual IPv4 gateway after the master fails and network staff think the IP must be changed manually.).

This option proposes: BFD exchanges lightweight control packets to test bidirectional forwarding paths and can notify registered clients such as routing processes; it is not itself a route-distribution protocol or a guarantee of link-physical failure. It addresses the different topic BFD rapid session detection and routing protocol association, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (An employee's workstation keeps sending to the configured virtual IPv4 gateway after the master fails and network staff think the IP must be changed manually.).

This option proposes: Inspect route sources, redistribution boundaries, attached route tags, candidate best paths and which protocol is currently advertising the problem prefix. It addresses the different topic Route redistribution feedback loops and route tags, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (An employee's workstation keeps sending to the configured virtual IPv4 gateway after the master fails and network staff think the IP must be changed manually.).

This option proposes: Inspect local and remote BFD configured minima, actual negotiated intervals, multiplier values, CPU pressure and observed detection timestamps. It addresses the different topic BFD detection multiplier and negotiated timers, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (An employee's workstation keeps sending to the configured virtual IPv4 gateway after the master fails and network staff think the IP must be changed manually.).

This option proposes: Inspect BFD discriminator and session state, timer negotiations, neighbor addresses, routing protocol binding and actual packet-loss observations. It addresses the different topic BFD rapid session detection and routing protocol association, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (An employee's workstation keeps sending to the configured virtual IPv4 gateway after the master fails and network staff think the IP must be changed manually.).

That option concerns BFD rapid session detection and routing protocol association. That follows from the targeted action: Check VRRP virtual IP and virtual MAC behavior while troubleshooting hosts that retain a stale default-gateway neighbor entry after failover.

That option concerns BFD detection multiplier and negotiated timers. That follows from the targeted action: Check VRRP virtual IP and virtual MAC behavior while troubleshooting hosts that retain a stale default-gateway neighbor entry after failover.

That option concerns Route-policy node and filtering direction. That follows from the targeted action: Check VRRP virtual IP and virtual MAC behavior while troubleshooting hosts that retain a stale default-gateway neighbor entry after failover.

This option proposes: Calculate or verify the practical failure-detection threshold from BFD transmit intervals, advertised receive intervals and the detect multiplier. It addresses the different topic BFD detection multiplier and negotiated timers, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (Two routers use incompatible VRRP group IDs on the same VLAN, causing confusing virtual-MAC behavior when users switch active gateways.).

This option proposes: Analyze Virtual Router Redundancy Protocol master election using priorities and the virtual router ID instead of a router's physical interface address alone. It addresses the different topic VRRP master election priority and tie breaks, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (Two routers use incompatible VRRP group IDs on the same VLAN, causing confusing virtual-MAC behavior when users switch active gateways.).

This option proposes: Configure DHCP relay to forward broadcast client discovery toward a reachable server and preserve the correct client-subnet context. It addresses the different topic DHCP relay across a routed user VLAN, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (Two routers use incompatible VRRP group IDs on the same VLAN, causing confusing virtual-MAC behavior when users switch active gateways.).

This option proposes: VRRP provides a shared virtual default-gateway identity, generally electing a higher-priority router as master while tie-breaking rules and address-owner behavior are relevant; hosts use the virtual address rather than the physical router selected by a static setting. It addresses the different topic VRRP master election priority and tie breaks, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (Two routers use incompatible VRRP group IDs on the same VLAN, causing confusing virtual-MAC behavior when users switch active gateways.).

This option proposes: BFD exchanges lightweight control packets to test bidirectional forwarding paths and can notify registered clients such as routing processes; it is not itself a route-distribution protocol or a guarantee of link-physical failure. It addresses the different topic BFD rapid session detection and routing protocol association, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (Two routers use incompatible VRRP group IDs on the same VLAN, causing confusing virtual-MAC behavior when users switch active gateways.).

This option proposes: A stateful firewall tracks valid connection context and can permit related return traffic based on session state; network ACLs may filter packets independently without the same stateful application tracking. It addresses the different topic Stateful firewall sessions versus basic packet ACL filtering, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (Two routers use incompatible VRRP group IDs on the same VLAN, causing confusing virtual-MAC behavior when users switch active gateways.).

This option proposes: Inspect local and remote BFD configured minima, actual negotiated intervals, multiplier values, CPU pressure and observed detection timestamps. It addresses the different topic BFD detection multiplier and negotiated timers, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (Two routers use incompatible VRRP group IDs on the same VLAN, causing confusing virtual-MAC behavior when users switch active gateways.).

This option proposes: Inspect AP discovery method, controller address reachability, CAPWAP control state, authorized AP inventory and configured service traffic forwarding mode. It addresses the different topic Large campus WLAN AC AP and CAPWAP architecture, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (Two routers use incompatible VRRP group IDs on the same VLAN, causing confusing virtual-MAC behavior when users switch active gateways.).

This option proposes: Review the monitored uplink state, tracked priority decrement, master/backup advertisements, preemption settings and return-path reachability. It addresses the different topic VRRP interface tracking and controlled preemption, not the directly tested VRRP virtual MAC and endpoint ARP continuity failure in the stated incident (Two routers use incompatible VRRP group IDs on the same VLAN, causing confusing virtual-MAC behavior when users switch active gateways.).

That option concerns VRRP interface tracking and controlled preemption. That follows from the targeted Recommended action: Check VRRP virtual IP and virtual MAC behavior while troubleshooting hosts that retain a stale default-gateway neighbor entry after failover.

That option concerns BFD detection multiplier and negotiated timers. That follows from the targeted Recommended action: Check VRRP virtual IP and virtual MAC behavior while troubleshooting hosts that retain a stale default-gateway neighbor entry after failover.

That option concerns MSTP region and VLAN-to-instance mappings. That follows from the targeted Recommended action: Check VRRP virtual IP and virtual MAC behavior while troubleshooting hosts that retain a stale default-gateway neighbor entry after failover.