Inspect peer reflect-client settings, received and advertised routes and RR topology. This check would diagnose BGP route-reflector client scoping, but would not first isolate the described Redistribution route tag loop avoidance. Begin with: Check route tags, source protocol, import-route statements and re-advertisement history.

Check PBR next hop, track state, route resolution and tested failure behavior. This check would diagnose PBR failed-next-hop fallback, but would not first isolate the described Redistribution route tag loop avoidance. Begin with: Check route tags, source protocol, import-route statements and re-advertisement history.

Inspect matching rule, applied attributes, selected route and resolved FIB next hop. This check would diagnose Route-policy next-hop and preference application, but would not first isolate the described Redistribution route tag loop avoidance. Begin with: Check route tags, source protocol, import-route statements and re-advertisement history.

Apply a reviewed community-filter match in the relevant import or export route-policy. This is a legitimate response to the different issue of BGP community filtering in routing control, but it does not correct the specific Route-policy next-hop and preference application condition reported. The relevant technical distinction is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

Design intended reflector cluster IDs and client relationships with loop-prevention attributes intact. This is a legitimate response to the different issue of BGP route reflector cluster loop prevention, but it does not correct the specific Route-policy next-hop and preference application condition reported. The relevant technical distinction is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

Set reviewed RSTP bridge priorities so an appropriate resilient core device remains root. This is a legitimate response to the different issue of RSTP root bridge location, but it does not correct the specific Route-policy next-hop and preference application condition reported. The relevant technical distinction is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

The preferred gateway is master under healthy conditions and backup is ready for takeover. That observation would support a separate case of VRRP priority and intended master, not verification of the reported Route-policy next-hop and preference application. The relevant observable outcome here is: Affected prefixes select the planned reachable next hop with correct preference while unrelated paths remain stable.

Matched voice flows receive the configured treatment and unrelated traffic remains within its approved class. That observation would support a separate case of MQC classifier and behavior association, not verification of the reported Route-policy next-hop and preference application. The relevant observable outcome here is: Affected prefixes select the planned reachable next hop with correct preference while unrelated paths remain stable.

A test prohibited prefix is rejected while authorized matching routes retain expected attributes. That observation would support a separate case of Route-policy permit and deny node order, not verification of the reported Route-policy next-hop and preference application. The relevant observable outcome here is: Affected prefixes select the planned reachable next hop with correct preference while unrelated paths remain stable.

Higher BGP LOCAL_PREF is normally preferred within an AS and is not advertised to external AS peers. This explains BGP local preference internal egress, but not why the issue in this scenario occurs. The specific mechanism is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

Policy-based routing can select forwarding based on packet attributes before conventional destination routing. This explains Policy-based routing for approved application, but not why the issue in this scenario occurs. The specific mechanism is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

QoS differentiation depends on packet classification, marking trust and congestion-aware queuing. This explains QoS DSCP remarking and trust, but not why the issue in this scenario occurs. The specific mechanism is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

An Established session with received prefixes can still leave routes unusable if next hops are unresolved. This consequence is associated more directly with iBGP next-hop reachability. For the stated conditions the immediate exposure is: An attribute-only change without forwarding checks can create a silent blackhole.

A permissive export filter can leak confidential topology and disrupt other routing domains. This consequence is associated more directly with BGP prefix export-filter leak. For the stated conditions the immediate exposure is: An attribute-only change without forwarding checks can create a silent blackhole.

Ignoring community-scoped policy can expose unintended network reachability. This consequence is associated more directly with BGP community filtering in routing control. For the stated conditions the immediate exposure is: An attribute-only change without forwarding checks can create a silent blackhole.

Audit security policy order, matching zones and addresses, and permitted-versus-denied test flows. This check would diagnose Default-deny network segmentation, but would not first isolate the described Route-policy next-hop and preference application. Begin with: Inspect matching rule, applied attributes, selected route and resolved FIB next hop.

Review ingress marks, traffic policy counters, queue occupancy and congestion test results. This check would diagnose QoS DSCP remarking and trust, but would not first isolate the described Route-policy next-hop and preference application. Begin with: Inspect matching rule, applied attributes, selected route and resolved FIB next hop.

Inspect ip-prefix sequence, mask-length qualifiers and test candidate routes. This check would diagnose Prefix-list network and mask matching, but would not first isolate the described Route-policy next-hop and preference application. Begin with: Inspect matching rule, applied attributes, selected route and resolved FIB next hop.

Apply a reviewed community-filter match in the relevant import or export route-policy. This is a legitimate response to the different issue of BGP community filtering in routing control, but it does not correct the specific Route-policy next-hop and preference application condition reported. The relevant technical distinction is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

Set reviewed RSTP bridge priorities so an appropriate resilient core device remains root. This is a legitimate response to the different issue of RSTP root bridge location, but it does not correct the specific Route-policy next-hop and preference application condition reported. The relevant technical distinction is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

Add supported PBR next-hop reachability tracking or failover logic consistent with service requirements. This is a legitimate response to the different issue of PBR failed-next-hop fallback, but it does not correct the specific Route-policy next-hop and preference application condition reported. The relevant technical distinction is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

A test prohibited prefix is rejected while authorized matching routes retain expected attributes. That observation would support a separate case of Route-policy permit and deny node order, not verification of the reported Route-policy next-hop and preference application. The relevant observable outcome here is: Affected prefixes select the planned reachable next hop with correct preference while unrelated paths remain stable.

The Level-1 area learns its required specifics while unrelated Level-2 routes stay outside its LSDB. That observation would support a separate case of IS-IS selective L2-to-L1 route leaking, not verification of the reported Route-policy next-hop and preference application. The relevant observable outcome here is: Affected prefixes select the planned reachable next hop with correct preference while unrelated paths remain stable.

Matched voice flows receive the configured treatment and unrelated traffic remains within its approved class. That observation would support a separate case of MQC classifier and behavior association, not verification of the reported Route-policy next-hop and preference application. The relevant observable outcome here is: Affected prefixes select the planned reachable next hop with correct preference while unrelated paths remain stable.

Centralized WLAN availability depends on AP-to-AC control-plane redundancy as well as RF coverage. This explains WLAN AC high availability, but not why the issue in this scenario occurs. The specific mechanism is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

Huawei MQC separates class identification, traffic behavior and applied traffic-policy binding. This explains MQC classifier and behavior association, but not why the issue in this scenario occurs. The specific mechanism is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

QoS differentiation depends on packet classification, marking trust and congestion-aware queuing. This explains QoS DSCP remarking and trust, but not why the issue in this scenario occurs. The specific mechanism is: Routing policy can alter selection attributes, but route installation still depends on next-hop reachability.

An accidental edge root can cause suboptimal paths and widespread topology changes. This consequence is associated more directly with RSTP root bridge location. For the stated conditions the immediate exposure is: An attribute-only change without forwarding checks can create a silent blackhole.

Misordered or misplaced ACLs can allow forbidden flows or deny legitimate services. This consequence is associated more directly with ACL packet filter rule order and direction. For the stated conditions the immediate exposure is: An attribute-only change without forwarding checks can create a silent blackhole.

Misunderstanding origin can lead to misleading troubleshooting changes to later attributes. This consequence is associated more directly with BGP origin attribute tie break. For the stated conditions the immediate exposure is: An attribute-only change without forwarding checks can create a silent blackhole.

Inspect stack role, heartbeat, split-brain detection state and inter-member link health. This check would diagnose Switch stacking split-brain, but would not first isolate the described Route-policy next-hop and preference application. Begin with: Inspect matching rule, applied attributes, selected route and resolved FIB next hop.

Check route tags, source protocol, import-route statements and re-advertisement history. This check would diagnose Redistribution route tag loop avoidance, but would not first isolate the described Route-policy next-hop and preference application. Begin with: Inspect matching rule, applied attributes, selected route and resolved FIB next hop.

Inspect PBR classifier, interface direction, policy hits and a traffic trace. This check would diagnose Policy-based routing for approved application, but would not first isolate the described Route-policy next-hop and preference application. Begin with: Inspect matching rule, applied attributes, selected route and resolved FIB next hop.