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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 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.).

This option proposes: Stacked switches can operate as a single logical device only while the supported control and data channels are consistent; a partition without dual-active detection risks conflicting forwarding or management identities. It addresses the different topic Switch stacking clustering and split-brain risk, 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: 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 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: 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 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: 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 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: 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 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: Compare the area link-state database, LSA type, advertising router, ABR reachability and route installation for the absent prefix. It addresses the different topic OSPF router network and summary LSA scope, 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.).

That option concerns Policy-based routing versus destination routing. That follows from the targeted Recommended 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 Recommended action: Design mutual route redistribution to prevent reimporting the same routes and changing their metrics repeatedly.

That option concerns Stateful firewall sessions versus basic packet ACL filtering. That follows from the targeted Recommended action: Design mutual route redistribution to prevent reimporting the same routes and changing their metrics repeatedly.

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 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: 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 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: Open unrestricted bidirectional traffic between every security zone because a return packet was dropped and assume stateful session tracking is irrelevant. It addresses the different topic Stateful firewall sessions versus basic packet ACL filtering, 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: 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 Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

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 Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

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 Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

This option proposes: MQC policy operation separates traffic classifiers, traffic behaviors and policies that bind them on a supported interface and direction; defining a classifier by itself does not apply a traffic action. It addresses the different topic Huawei MQC traffic classification and behavior binding, not the directly tested Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

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 Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

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 Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

This option proposes: Review each node sequence, if-match clauses, apply actions and import/export attachment for the affected routing session. It addresses the different topic Route-policy node and filtering direction, not the directly tested Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

This option proposes: Inspect VRRP group ID, configured virtual IP, device priorities, master/backup state and advertisements on both routers. It addresses the different topic VRRP master election priority and tie breaks, not the directly tested Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

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 Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

That option concerns Route-policy node and filtering direction. That follows from the targeted action: Differentiate traffic policy-based routing on a matching packet from ordinary destination-based forwarding through the best RIB route.

That option concerns SDN WAN control and SD-WAN policy forwarding. That follows from the targeted action: Differentiate traffic policy-based routing on a matching packet from ordinary destination-based forwarding through the best RIB route.

That option concerns ACL traffic filter placement and rule order. That follows from the targeted action: Differentiate traffic policy-based routing on a matching packet from ordinary destination-based forwarding through the best RIB route.

This option proposes: Configure a Source-Specific Multicast receiver with only an unspecified group and assume no source identity information is ever required. It addresses the different topic IGMPv3 source-specific selection and SSM, not the directly tested Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

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 Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

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 Policy-based routing versus destination routing failure in the stated incident (A hospital needs backup traffic to use a low-cost WAN link while production medical traffic must stay on a guaranteed circuit despite sharing a destination prefix.).

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 Policy-based routing versus destination routing failure in the stated incident (An engineer deploys a policy route for one subnet but sees unmatched traffic still use the global best route and mistakenly considers that a failure.).

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 Policy-based routing versus destination routing failure in the stated incident (An engineer deploys a policy route for one subnet but sees unmatched traffic still use the global best route and mistakenly considers that a failure.).

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 Policy-based routing versus destination routing failure in the stated incident (An engineer deploys a policy route for one subnet but sees unmatched traffic still use the global best route and mistakenly considers that a failure.).