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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 MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

This option proposes: Diagnose a multicast drop by checking reverse path forwarding against the packet's source rather than only validating the destination group. It addresses the different topic Multicast reverse path forwarding checks, not the directly tested MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

This option proposes: Analyze BGP best-path choices in a specified platform and release before deciding that the shortest AS_PATH alone always wins. It addresses the different topic BGP route preference sequence and policy precedence, not the directly tested MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

This option proposes: BGP path validity requires next-hop reachability; iBGP may preserve an eBGP-learned next hop, so a next-hop-self design can make that address reachable through the IGP where appropriate. It addresses the different topic BGP NEXT_HOP reachability and next-hop-self, not the directly tested MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

This option proposes: BGP communities carry policy markers that can be matched by participating peers, but the markers alone do not enforce filtering unless suitable route-policy rules recognize and act on them. It addresses the different topic BGP community tagging and route-policy control, not the directly tested MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

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 MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

This option proposes: Inspect candidate routes' neighboring AS, MED values, other higher-priority attributes and local comparison configuration. It addresses the different topic BGP MED interpretation between neighboring autonomous systems, not the directly tested MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

This option proposes: Inspect the active RIB prefix and mask, BGP network or import-route configuration, route-policy matches and outbound Adj-RIB-Out to the peer. It addresses the different topic BGP route origin network and redistribution policy, not the directly tested MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

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 MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

That option concerns BGP route preference sequence and policy precedence. That follows from the targeted Recommended action: Distinguish EVPN control-plane route information and underlay forwarding when analyzing a VXLAN-enabled fabric.

That option concerns BGP route reflector and cluster loop prevention. That follows from the targeted Recommended action: Distinguish EVPN control-plane route information and underlay forwarding when analyzing a VXLAN-enabled fabric.

That option concerns OSPF backbone connectivity and virtual link design. That follows from the targeted Recommended action: Distinguish EVPN control-plane route information and underlay forwarding when analyzing a VXLAN-enabled fabric.

This option proposes: Declare that setting MED to zero guarantees every Internet autonomous system will send traffic through that link regardless of local preference or AS_PATH. It addresses the different topic BGP MED interpretation between neighboring autonomous systems, not the directly tested MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

This option proposes: Assume a BGP network statement advertises any imagined aggregate even when no corresponding active local route exists or suitable aggregate mechanism is configured. It addresses the different topic BGP route origin network and redistribution policy, not the directly tested MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

This option proposes: Assume the switch with the fastest interface always becomes the spanning-tree root even when a lower bridge ID exists elsewhere. It addresses the different topic RSTP designated root and backup topology selection, not the directly tested MP-BGP EVPN route types and forwarding separation failure in the stated incident (A tenant's Type 5 prefix appears in the BGP EVPN table but is not imported into the intended service VRF because route targets do not match.).

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 IP prefix filtering and exact route-match conditions failure in the stated incident (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.).

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 IP prefix filtering and exact route-match conditions failure in the stated incident (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.).

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 (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.).

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 IP prefix filtering and exact route-match conditions failure in the stated incident (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.).

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 (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.).

This option proposes: MED is an optional nontransitive BGP attribute, with lower values typically favored when compared under applicable rules; it is often compared for routes from the same neighboring AS unless policy changes this behavior. It addresses the different topic BGP MED interpretation between neighboring autonomous systems, not the directly tested IP prefix filtering and exact route-match conditions failure in the stated incident (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.).

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 IP prefix filtering and exact route-match conditions failure in the stated incident (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.).

This option proposes: Review RA source, autonomous prefix flag, valid and preferred lifetimes, DAD NS traffic, address state and default router list. It addresses the different topic IPv6 SLAAC RA prefix and duplicate address detection, not the directly tested IP prefix filtering and exact route-match conditions failure in the stated incident (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.).

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 (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.).

That option concerns Policy-based routing versus destination routing. That follows from the targeted 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 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 OSPF interface security and passive network advertisement. That follows from the targeted 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: 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 (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.). The better discriminating check for this case is: Inspect the prefix-list rule sequence, base prefix, greater-than/less-than mask conditions and test routes immediately inside and outside the intended range.

This option proposes: Diagnose outbound path choice across iBGP speakers using locally distributed LOCAL_PREF values. It addresses the different topic BGP LOCAL_PREF within one autonomous system, not the directly tested IP prefix filtering and exact route-match conditions failure in the stated incident (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.).

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 IP prefix filtering and exact route-match conditions failure in the stated incident (An enterprise wants to announce customer networks within 10.40.0.0/16 only when each subnet is a /24, but an existing filter unexpectedly matches a /20.).

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.).