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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 IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

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 IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

This option proposes: Explain how PIM dense mode initially distributes traffic and then prunes interfaces lacking downstream receivers. It addresses the different topic PIM dense mode flooding and prune mechanisms, not the directly tested IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

This option proposes: An NSSA permits its local ASBR to originate type 7 external LSAs that can be translated to type 5 by an eligible ABR, while incoming external type 5 advertisements are not flooded into the NSSA. It addresses the different topic NSSA type seven translation and default routing, not the directly tested IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

This option proposes: Huawei route-policy processing applies matching conditions and actions in sequence, and unmatched or explicitly denied routes can be rejected depending on the policy context; inbound and outbound application points are not interchangeable. It addresses the different topic Route-policy node and filtering direction, not the directly tested IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

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 IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

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 IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

This option proposes: Inspect primary/backup controller registrations, AP failover behavior, RADIUS/802.1X results, user authorization attributes and policy applied to a test client. It addresses the different topic WLAN controller redundancy and NAC integration, not the directly tested IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

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 IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

That option concerns IPsec VPN IKE negotiation versus ESP data channel. That follows from the targeted Recommended action: Use a carefully scoped Huawei IP prefix list to match the intended route ranges and prefix lengths before applying an import or export policy.

That option concerns Route redistribution feedback loops and route tags. That follows from the targeted Recommended action: Use a carefully scoped Huawei IP prefix list to match the intended route ranges and prefix lengths before applying an import or export policy.

That option concerns Route-policy node and filtering direction. That follows from the targeted Recommended action: Use a carefully scoped Huawei IP prefix list to match the intended route ranges and prefix lengths before applying an import or export policy.

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 IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

This option proposes: Place an any-any deny first in a production ACL and assume later narrower permits will always override it regardless of matching order. It addresses the different topic ACL traffic filter placement and rule order, not the directly tested IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

This option proposes: Attempt to configure an OSPF BDR role for IS-IS, assuming the DIS cannot operate until a backup DIS has been selected. It addresses the different topic IS-IS designated intermediate system and pseudonode, not the directly tested IP prefix filtering and exact route-match conditions failure in the stated incident (A branch route-policy accepts 172.20.0.0/16 and engineers discover that 172.20.48.0/24 is excluded because the prefix-length range was too narrow.).

This option proposes: Diagnose a packet-forwarding discrepancy by separating control-plane routes recorded in the RIB from hardware or software forwarding entries installed in the FIB. It addresses the different topic Network forwarding planes RIB versus FIB, not the directly tested Route-policy node and filtering direction failure in the stated incident (A BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

This option proposes: Verify the match criteria and behavior binding in a Modular QoS Command-Line configuration before investigating packet-marking or policing failures. 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 BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

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 BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

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 BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

This option proposes: SNMP managers request device state, while traps and informs carry event notifications; SNMPv3 offers user-based authentication and optional privacy protection unlike insecure shared-community assumptions. It addresses the different topic SNMP manager polling traps and authenticated operation, not the directly tested Route-policy node and filtering direction failure in the stated incident (A BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

This option proposes: Huawei ACL filtering considers rule order and match criteria; permit or deny decisions depend on the traffic-filter feature and where the ACL is applied, so a symmetric assumption about directions can be wrong. 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 BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

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 BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

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-policy node and filtering direction failure in the stated incident (A BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

This option proposes: Inspect the originating ASBR, type 5 LSA, external metric type and metric, cost toward the ASBR and actual selected external next hop. It addresses the different topic OSPF external LSAs and E1 versus E2 cost, not the directly tested Route-policy node and filtering direction failure in the stated incident (A BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

That option concerns Route redistribution feedback loops and route tags. That follows from the targeted action: Check route-policy matching conditions, node permit/deny behavior and application direction before fixing unexpected accepted or rejected routes.

That option concerns Network forwarding planes RIB versus FIB. That follows from the targeted action: Check route-policy matching conditions, node permit/deny behavior and application direction before fixing unexpected accepted or rejected routes.

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

This option proposes: Ensure consistent MST region name, revision and VLAN-to-instance mapping before expecting switches to share the same spanning-tree instance topology. It addresses the different topic MSTP region and VLAN-to-instance mappings, not the directly tested Route-policy node and filtering direction failure in the stated incident (A BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

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-policy node and filtering direction failure in the stated incident (A BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

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 Route-policy node and filtering direction failure in the stated incident (A BGP engineer creates a permit node for authorized networks but an earlier deny node drops the same prefixes before the later node is considered.).

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.).