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This option proposes: Differentiate traffic policy-based routing on a matching packet from ordinary destination-based forwarding through the best RIB route. It addresses the different topic Policy-based routing versus destination routing, not the directly tested Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

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 Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

This option proposes: Configure VRRP priority tracking with suitable preemption behavior so loss of upstream connectivity changes the preferred gateway. It addresses the different topic VRRP interface tracking and controlled preemption, not the directly tested Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

This option proposes: PBR can steer selected packets based on additional attributes such as source or application criteria, with fallback behavior defined by policy; it does not require the routing protocol to advertise a new destination prefix. It addresses the different topic Policy-based routing versus destination routing, not the directly tested Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

This option proposes: Prefix filters can test network address plus mask range, and permit or deny effects depend on how the list is referenced; a matching address alone does not imply every more-specific subnet is included. It addresses the different topic IP prefix filtering and exact route-match conditions, not the directly tested Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

This option proposes: Packet selection uses the most-specific matching destination route before comparing candidate protocol preferences for identical prefixes; a broad default route does not displace a more-specific valid route solely by lower preference. It addresses the different topic Longest prefix match and route preferences, not the directly tested Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

This option proposes: Review packet source and destination fields, rule sequence, actual interface ingress or egress attachment and matching counters. It addresses the different topic ACL traffic filter placement and rule order, not the directly tested Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

This option proposes: Inspect the destination address, matching installed prefixes, their mask lengths, route sources, next-hop resolution and the forwarding decision. It addresses the different topic Longest prefix match and route preferences, not the directly tested Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

This option proposes: Inspect classifier match counters, behavior actions, traffic-policy associations, interface attachment and ingress/egress direction. It addresses the different topic Huawei MQC traffic classification and behavior binding, not the directly tested Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

That option concerns ACL traffic filter placement and rule order. That follows from the targeted Recommended action: Check route-policy matching conditions, node permit/deny behavior and application direction before fixing unexpected accepted or rejected routes.

That option concerns Huawei MQC traffic classification and behavior binding. That follows from the targeted Recommended action: Check route-policy matching conditions, node permit/deny behavior and application direction before fixing unexpected accepted or rejected routes.

That option concerns OSPF SPF calculation and interface cost changes. That follows from the targeted Recommended action: Check route-policy matching conditions, node permit/deny behavior and application direction before fixing unexpected accepted or rejected routes.

This option proposes: Assume that configuring a multicast source anywhere in the network automatically populates IGMP membership on a VLAN where no receiver has joined. It addresses the different topic IGMP querier membership reports and group timeout, not the directly tested Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

This option proposes: Apply a permissive 0.0.0.0/0 catch-all prefix rule as an emergency fix for one missing route without examining how it affects unrelated advertised networks. It addresses the different topic IP prefix filtering and exact route-match conditions, not the directly tested Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

This option proposes: Create a traffic classifier matching voice packets and assume that alone guarantees priority scheduling without any traffic behavior or attached policy. It addresses the different topic Huawei MQC traffic classification and behavior binding, not the directly tested Route-policy node and filtering direction failure in the stated incident (A redistribution change works on one edge but leaks a management prefix on another because the route-policy was applied to the wrong direction.).

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 Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.).

This option proposes: Trace ACL rule matching and interface direction before broadening a security filter that drops legitimate traffic. It addresses the different topic ACL traffic filter placement and rule order, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.).

This option proposes: Differentiate traffic policy-based routing on a matching packet from ordinary destination-based forwarding through the best RIB route. It addresses the different topic Policy-based routing versus destination routing, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.).

This option proposes: A stub area blocks type 5 external LSAs and receives an appropriate default through its ABR; a totally stubby configuration additionally suppresses most inter-area summaries and is incompatible with certain topology roles. It addresses the different topic Stub and totally stub area restrictions, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.).

This option proposes: Prefix filters can test network address plus mask range, and permit or deny effects depend on how the list is referenced; a matching address alone does not imply every more-specific subnet is included. It addresses the different topic IP prefix filtering and exact route-match conditions, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.).

This option proposes: PBR can steer selected packets based on additional attributes such as source or application criteria, with fallback behavior defined by policy; it does not require the routing protocol to advertise a new destination prefix. It addresses the different topic Policy-based routing versus destination routing, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.).

This option proposes: Inspect the prefix-list rule sequence, base prefix, greater-than/less-than mask conditions and test routes immediately inside and outside the intended range. It addresses the different topic IP prefix filtering and exact route-match conditions, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.).

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 Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.).

This option proposes: Check DR and BDR addresses, each neighbor's interface priority and router ID, network type and whether an election actually occurred. It addresses the different topic OSPF broadcast DR and BDR election, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.).

That option concerns WLAN VLAN pools and DHCP address scopes. That follows from the targeted action: Design mutual route redistribution to prevent reimporting the same routes and changing their metrics repeatedly.

That option concerns Huawei MQC traffic classification and behavior binding. That follows from the targeted action: Design mutual route redistribution to prevent reimporting the same routes and changing their metrics repeatedly.

That option concerns Route-policy node and filtering direction. That follows from the targeted action: Design mutual route redistribution to prevent reimporting the same routes and changing their metrics repeatedly.

This option proposes: Assess fast roaming within and between AP coverage cells using the configured mobility relationship and authentication requirements. It addresses the different topic Wireless roaming mobility and session continuity, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.).

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 Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.). The better discriminating check for this case is: Inspect route sources, redistribution boundaries, attached route tags, candidate best paths and which protocol is currently advertising the problem prefix.

This option proposes: Evaluate non-backbone OSPF connectivity through area 0 and whether a virtual link is an appropriate temporary correction in supported topologies. It addresses the different topic OSPF backbone connectivity and virtual link design, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (An enterprise connects two OSPF regions through IS-IS at two sites, then sees a campus route repeatedly change its origin after broad mutual redistribution.).

This option proposes: Check the MED value and the policy context before using BGP advertisements to suggest which entry link another AS should prefer. It addresses the different topic BGP MED interpretation between neighboring autonomous systems, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (A network operator uses route tags to prevent an external prefix returning to its source domain but forgets to match the tag on the reverse import policy.).

This option proposes: Differentiate traffic policy-based routing on a matching packet from ordinary destination-based forwarding through the best RIB route. It addresses the different topic Policy-based routing versus destination routing, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (A network operator uses route tags to prevent an external prefix returning to its source domain but forgets to match the tag on the reverse import policy.).

This option proposes: Check route-policy matching conditions, node permit/deny behavior and application direction before fixing unexpected accepted or rejected routes. It addresses the different topic Route-policy node and filtering direction, not the directly tested Route redistribution feedback loops and route tags failure in the stated incident (A network operator uses route tags to prevent an external prefix returning to its source domain but forgets to match the tag on the reverse import policy.).