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This option proposes: Inspect the received AS_PATH, origin AS, eBGP neighbor AS, policy additions and route-selection evidence before changing prepend counts. It addresses the different topic BGP AS_PATH path-vector loop prevention, not the directly tested BFD detection multiplier and negotiated timers failure in the stated incident (A backbone change request claims a 300 ms failure threshold, but the operating BFD session uses a 100 ms negotiated interval and a detect multiplier of five.). The better discriminating check for this case is: Inspect local and remote BFD configured minima, actual negotiated intervals, multiplier values, CPU pressure and observed detection timestamps. The targeted correction is: Calculate or verify the practical failure-detection threshold from BFD transmit intervals, advertised receive intervals and the detect multiplier.

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 BFD detection multiplier and negotiated timers failure in the stated incident (A backbone change request claims a 300 ms failure threshold, but the operating BFD session uses a 100 ms negotiated interval and a detect multiplier of five.).

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 BFD detection multiplier and negotiated timers failure in the stated incident (A backbone change request claims a 300 ms failure threshold, but the operating BFD session uses a 100 ms negotiated interval and a detect multiplier of five.).

That option concerns VRRP master election priority and tie breaks. That follows from the targeted Recommended action: Calculate or verify the practical failure-detection threshold from BFD transmit intervals, advertised receive intervals and the detect multiplier.

That option concerns VRRP interface tracking and controlled preemption. That follows from the targeted Recommended action: Calculate or verify the practical failure-detection threshold from BFD transmit intervals, advertised receive intervals and the detect multiplier.

That option concerns Route-policy node and filtering direction. That follows from the targeted Recommended action: Calculate or verify the practical failure-detection threshold from BFD transmit intervals, advertised receive intervals and the detect multiplier.

This option proposes: Use a carefully scoped Huawei IP prefix list to match the intended route ranges and prefix lengths before applying an import or export policy. It addresses the different topic IP prefix filtering and exact route-match conditions, not the directly tested BFD detection multiplier and negotiated timers failure in the stated incident (A backbone change request claims a 300 ms failure threshold, but the operating BFD session uses a 100 ms negotiated interval and a detect multiplier of five.).

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 BFD detection multiplier and negotiated timers failure in the stated incident (A backbone change request claims a 300 ms failure threshold, but the operating BFD session uses a 100 ms negotiated interval and a detect multiplier of five.).

This option proposes: Inspect compatible IS-IS NET area IDs, interface levels and authentication before changing a routing process after adjacency failure. It addresses the different topic IS-IS area addresses and adjacency prerequisites, not the directly tested BFD detection multiplier and negotiated timers failure in the stated incident (A backbone change request claims a 300 ms failure threshold, but the operating BFD session uses a 100 ms negotiated interval and a detect multiplier of five.). The better discriminating check for this case is: Inspect local and remote BFD configured minima, actual negotiated intervals, multiplier values, CPU pressure and observed detection timestamps.

This option proposes: Use Bidirectional Forwarding Detection to provide rapid validated failure indications to a supported routing or redundancy protocol. It addresses the different topic BFD rapid session detection and routing protocol association, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

This option proposes: Check IGMP membership and querier operation on the receiver LAN before changing PIM routing configuration upstream. It addresses the different topic IGMP querier membership reports and group timeout, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

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 master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

This option proposes: VRRP uses a virtual router identity and virtual MAC per IPv4 group to preserve a stable next-hop identity across master changes; correct failover still requires matching VLAN, neighbor learning and eligible router state. It addresses the different topic VRRP virtual MAC and endpoint ARP continuity, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

This option proposes: WLAN roaming is a client transition between APs, and preserving service depends on consistent SSID/security configuration, mobility coordination and the chosen network architecture, not simply RF overlap. It addresses the different topic Wireless roaming mobility and session continuity, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

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 master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

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 master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

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 master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

This option proposes: Compare WLAN service templates, VLAN pool membership and assignment method, gateway/SVI, relay configuration and per-VLAN available leases. It addresses the different topic WLAN VLAN pools and DHCP address scopes, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

That option concerns BGP route preference sequence and policy precedence. That follows from the targeted action: Analyze Virtual Router Redundancy Protocol master election using priorities and the virtual router ID instead of a router's physical interface address alone.

That option concerns VRRP virtual MAC and endpoint ARP continuity. That follows from the targeted action: Analyze Virtual Router Redundancy Protocol master election using priorities and the virtual router ID instead of a router's physical interface address alone.

That option concerns BFD rapid session detection and routing protocol association. That follows from the targeted action: Analyze Virtual Router Redundancy Protocol master election using priorities and the virtual router ID instead of a router's physical interface address alone.

This option proposes: Edit route attributes in an unused route-policy and assume the live BGP session will automatically enforce those rules without an import or export attachment. It addresses the different topic Route-policy node and filtering direction, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

This option proposes: Track only the host-facing VRRP VLAN while ignoring the active master's failed upstream WAN and insist the gateway must remain preferred regardless of reachability. It addresses the different topic VRRP interface tracking and controlled preemption, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

This option proposes: Require every desktop to change its configured default gateway to the backup router's physical interface address immediately after each VRRP election. It addresses the different topic VRRP virtual MAC and endpoint ARP continuity, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (Two campus gateways both advertise VRRP group 10, but their priorities were reversed during maintenance and the backup unexpectedly becomes master.).

This option proposes: Validate resilient AC roles and per-user access decisions when WLAN controller failure or endpoint authorization affects service. It addresses the different topic WLAN controller redundancy and NAC integration, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (A high-availability deployment uses the same virtual gateway address on both routers yet one device remains in Initialize because the interface is administratively down.).

This option proposes: Use Bidirectional Forwarding Detection to provide rapid validated failure indications to a supported routing or redundancy protocol. It addresses the different topic BFD rapid session detection and routing protocol association, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (A high-availability deployment uses the same virtual gateway address on both routers yet one device remains in Initialize because the interface is administratively down.).

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 master election priority and tie breaks failure in the stated incident (A high-availability deployment uses the same virtual gateway address on both routers yet one device remains in Initialize because the interface is administratively down.).

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 master election priority and tie breaks failure in the stated incident (A high-availability deployment uses the same virtual gateway address on both routers yet one device remains in Initialize because the interface is administratively down.).

This option proposes: In any-source PIM-SM an RP supports initial shared-tree joining and source registration, while routers may switch to source-rooted shortest-path trees according to configured behavior and traffic. It addresses the different topic PIM sparse mode RP shared tree and shortest path transition, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (A high-availability deployment uses the same virtual gateway address on both routers yet one device remains in Initialize because the interface is administratively down.).

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 master election priority and tie breaks failure in the stated incident (A high-availability deployment uses the same virtual gateway address on both routers yet one device remains in Initialize because the interface is administratively down.).

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 master election priority and tie breaks failure in the stated incident (A high-availability deployment uses the same virtual gateway address on both routers yet one device remains in Initialize because the interface is administratively down.).

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 master election priority and tie breaks failure in the stated incident (A high-availability deployment uses the same virtual gateway address on both routers yet one device remains in Initialize because the interface is administratively down.).

This option proposes: Inspect the received AS_PATH, origin AS, eBGP neighbor AS, policy additions and route-selection evidence before changing prepend counts. It addresses the different topic BGP AS_PATH path-vector loop prevention, not the directly tested VRRP master election priority and tie breaks failure in the stated incident (A high-availability deployment uses the same virtual gateway address on both routers yet one device remains in Initialize because the interface is administratively down.). The better discriminating check for this case is: Inspect VRRP group ID, configured virtual IP, device priorities, master/backup state and advertisements on both routers. The targeted correction is: Analyze Virtual Router Redundancy Protocol master election using priorities and the virtual router ID instead of a router's physical interface address alone.