Traffic mirroring copies eligible packets to a collector for protocol-level inspection that flow logs cannot perform; this belongs to deep packet analysis of mirrored instance traffic, while the problem is separating packet acceptance from HTTP service failure.

Flow-log action provides packet-acceptance evidence, while the applicable security group and network ACL configurations identify the likely admission control to investigate; this changes diagnosing admission failure from VPC flow metadata, not the necessary separating packet acceptance from HTTP service failure.

In the transport reset correlation for NLB-backed services workflow, transport-layer reset counters help separate load-balancer and target behaviors from generic HTTP response metrics; the current case needs separating packet acceptance from HTTP service failure.

Long-lived idle connections can be closed when connection-idle periods exceed configured timeouts even while new handshakes succeed; that addresses idle connection lifetimes in load-balanced applications, rather than packet-size-specific hybrid connectivity diagnosis.

Accepted network flows do not guarantee a successful HTTP response; layer-seven errors require service and target investigation; this belongs to separating packet acceptance from HTTP service failure, while the problem is packet-size-specific hybrid connectivity diagnosis.

Network Manager combines global network attachment context and route analysis to expose connectivity paths beyond single-ENI flow records; this changes hybrid network topology and route-path correlation, not the necessary packet-size-specific hybrid connectivity diagnosis.

This produces configuration-based path blockage analysis: Reachability Analyzer statically identifies route, ACL, and security-group constraints for supported paths without packet capture; the stem instead tests packet-size-specific hybrid connectivity diagnosis.

Flow Logs describe observed IP traffic at supported VPC interfaces; they do not trace each hop through Transit Gateway route tables or model reverse attachment paths.

CloudFront logs concern HTTP viewer and edge behavior. They have no access to Transit Gateway attachment associations or propagated IP routes.

Target health identifies application target availability, not the TGW routing tables used for transit attachment lookup or end-to-end return-path analysis.

Link health and routing adjacency are distinct; the VIF-specific metrics expose session-level problems hidden by a healthy physical connection; that addresses isolating Direct Connect control-plane faults, rather than hybrid network topology and route-path correlation.

Reachability Analyzer statically identifies route, ACL, and security-group constraints for supported paths without packet capture; this belongs to configuration-based path blockage analysis, while the problem is hybrid network topology and route-path correlation.

In the validation of networking change impacts workflow, reproducible path analysis around a change identifies the network control that altered connectivity intent; the current case needs hybrid network topology and route-path correlation.

Traffic Mirroring uses VXLAN encapsulated over UDP port 4789. Opening TCP on that port does not permit the UDP datagrams that carry the mirrored packet copies.

The payload can represent HTTPS traffic, but the transport to the traffic-mirror target is a distinct outer VXLAN-over-UDP packet. Permitting only the original application port is insufficient.

Flow Logs summarize packet-flow metadata; they cannot deliver mirrored packet payloads or bypass the sensor security group that rejects VXLAN packets.

Network Manager combines global network attachment context and route analysis to expose connectivity paths beyond single-ENI flow records; that addresses hybrid network topology and route-path correlation, rather than isolating Direct Connect control-plane faults.

Transport-layer reset counters help separate load-balancer and target behaviors from generic HTTP response metrics; this belongs to transport reset correlation for NLB-backed services, while the problem is isolating Direct Connect control-plane faults.

In the validation of networking change impacts workflow, reproducible path analysis around a change identifies the network control that altered connectivity intent; the current case needs isolating Direct Connect control-plane faults.

Zonal eligibility and target placement determine which NLB node can forward to healthy registered endpoints; that addresses per-AZ load-balancer target failure analysis, rather than transport reset correlation for NLB-backed services.

Accepted network flows do not guarantee a successful HTTP response; layer-seven errors require service and target investigation; this changes separating packet acceptance from HTTP service failure, not the necessary transport reset correlation for NLB-backed services.

In the ALB upstream connection failures workflow, A load balancer can fail to establish or maintain the backend HTTP connection even when the client successfully reaches the ALB listener; the current case needs transport reset correlation for NLB-backed services.

Public DNS would reveal private names and does not make the custom internal resolver aware of authoritative VPC-private records. The private data should be resolved through the VPC DNS service.

A gateway endpoint affects network routes for supported S3 requests, not where an operating-system DNS resolver sends queries for a Route 53 private hosted zone.

Disabling VPC DNS support prevents use of AmazonProvidedDNS for the zone, which is the working path in the scenario. It does not repair the custom resolver’s missing private-namespace route.

A longer cache TTL can prolong stale or negative responses. The cause is the custom resolver path, not instability of the correctly associated private-zone authoritative records.

Transport-layer reset counters help separate load-balancer and target behaviors from generic HTTP response metrics; that addresses transport reset correlation for NLB-backed services, rather than ALB upstream connection failures.

TLS policy and certificate configuration govern the client-to-ALB handshake; healthy instances cannot repair an incompatible edge negotiation; this changes frontend TLS compatibility diagnosis, not the necessary ALB upstream connection failures.

In the separating packet acceptance from HTTP service failure workflow, accepted network flows do not guarantee a successful HTTP response; layer-seven errors require service and target investigation; the current case needs ALB upstream connection failures.

Reproducible path analysis around a change identifies the network control that altered connectivity intent; that addresses validation of networking change impacts, rather than authoritative-versus-cached DNS response diagnosis.

DNS suffix mapping and resolver endpoint routing both must be correct before an external target receives the query; this belongs to rule-to-endpoint hybrid DNS forwarding trace, while the problem is authoritative-versus-cached DNS response diagnosis.

In the scope of private DNS resolver visibility workflow, correct zone data cannot be seen by a VPC outside the relevant association scope or with incompatible VPC DNS settings; the current case needs authoritative-versus-cached DNS response diagnosis.

Transport-layer reset counters help separate load-balancer and target behaviors from generic HTTP response metrics; that addresses transport reset correlation for NLB-backed services, rather than zonal isolation of network performance anomalies.

Zonal eligibility and target placement determine which NLB node can forward to healthy registered endpoints; this changes per-AZ load-balancer target failure analysis, not the necessary zonal isolation of network performance anomalies.

In the scope of private DNS resolver visibility workflow, correct zone data cannot be seen by a VPC outside the relevant association scope or with incompatible VPC DNS settings; the current case needs zonal isolation of network performance anomalies.

This produces isolating Direct Connect control-plane faults: Link health and routing adjacency are distinct; the VIF-specific metrics expose session-level problems hidden by a healthy physical connection; the stem instead tests zonal isolation of network performance anomalies.

For limits of static configuration path analysis, A modeled permissible network path does not establish that a process is listening, credentials are accepted, or runtime packet loss is absent; however, the present requirement is zonal isolation of network performance anomalies.