Question 400
A global static website is overwhelmed by repeated edge-reachable object requests from many regions. How should this network requirement be implemented?
- Use AWS Shield Standard protections built into eligible AWS infrastructure
- Cache eligible responses through CloudFront with suitable protections
- Use Shield Advanced event visibility and configured notifications
- Use AWS WAF rules alongside Shield DDoS defenses
Explanation
Correct Answer
B:The approach distributes content delivery across the CDN edge infrastructure; forcing all requests directly to one EC2 origin retains a central bottleneck, directly enabling scalable edge absorption of repeated web requests in this situation.
Incorrect Answers
A:This alternative supplies baseline protection against common network and transport DDoS events; a custom WAF rule is not a general replacement for underlying network volumetric mitigation, so it addresses default AWS DDoS protection coverage rather than the required scalable edge absorption of repeated web requests.
C:The proposed action tracks observed DDoS attack events for protected resources; generic application logs alone may not classify infrastructure-level DDoS events, supporting auditable advanced DDoS response monitoring but leaving scalable edge absorption of repeated web requests unmet.
D:This approach filters application-layer requests based on HTTP properties; pure network-layer shielding cannot express arbitrary header or URI rules, which helps with layer-seven request mitigation in a DDoS defense strategy instead of delivering scalable edge absorption of repeated web requests.
Question 401
A production data center has one AWS Direct Connect connection and must survive its loss using existing firewalls. What should the network specialist configure?
- Review BGP preferences and advertisements on both circuits
- Review longest-prefix selection before applying BGP preference changes
- Simulate primary Direct Connect failure and observe BGP route convergence
- Enable and validate VPN ECMP with appropriate dynamic routes on the TGW
- Deploy Site-to-Site VPN as a failover path and adjust routing priorities
Explanation
Correct Answer
E:This configuration retains an alternate IPsec path when the primary private circuit becomes unavailable; both primary and backup must advertise compatible destinations with sensible preference, so it delivers backup hybrid routing over an independent transport under the stated constraints.
Incorrect Answers
A:This approach determines which valid session's routes are selected and available for backup; additional physical links do not force desired routing distribution, which helps with correct primary-secondary Direct Connect behavior instead of delivering backup hybrid routing over an independent transport.
B:This alternative recognizes that more-specific routing matches can override broad path preference; comparing AS_PATH for different-length prefixes does not override destination longest-match logic, so it addresses predictable forwarding with mixed BGP prefix lengths rather than the required backup hybrid routing over an independent transport.
C:Although this setting verifies that the alternate tunnel carries real traffic when the preferred path disappears, an idle VPN status page alone is not evidence of end-to-end recovery; this concerns tested hybrid link failover, not the specified backup hybrid routing over an independent transport.
D:The proposed action allows eligible equivalent VPN routes to share flows using transit gateway ECMP; ECMP requires compatible dynamic routing and does not make the internet transport deterministic, supporting supported multipath use of VPN tunnels but leaving backup hybrid routing over an independent transport unmet.
Question 402
A performance team sees user complaints after healthy backends move Region; old clients keep contacting previous IPs. Which change is the most appropriate?
- Set suitable cache TTL controls consistent with origin Cache-Control headers
- Reduce applicable DNS TTLs before planned changes and consider stable anycast ingress where required
- Reduce needless cache-key dimensions in the CloudFront cache policy
- Use AWS Global Accelerator for supported regional application endpoints
Explanation
Correct Answer
B:With this choice, the selected action limits the duration of stale DNS answers during endpoint migrations; lowering a TTL after clients already cache a larger value cannot retroactively expire those caches, providing managed DNS cutover convergence for the network described.
Incorrect Answers
A:The proposed action permits safe edge reuse of static responses for a defined period; caching private personalized responses by extending TTL would be unsafe, supporting fewer unnecessary origin fetches but leaving managed DNS cutover convergence unmet.
C:This alternative shares equivalent cached responses across more viewer requests; necessary content-variation dimensions must remain in the key to prevent incorrect responses, so it addresses improved CDN cache efficiency rather than the required managed DNS cutover convergence.
D:Although this setting routes traffic into the AWS backbone through anycast edge addresses, caching with CloudFront is a different optimization for eligible HTTP objects; this concerns global dynamic-traffic ingress optimization, not the specified managed DNS cutover convergence.
Question 403
A cloud engineer wants a static explanation for why source ENI traffic cannot reach a destination ENI given the configured AWS path. What is the most suitable design or configuration?
- Use AWS Network Manager network topology and monitoring features
- Create a CloudWatch alarm on the relevant Direct Connect metric
- Enable the appropriate load balancer access logs
- Run VPC Reachability Analyzer between the selected endpoints
Explanation
Correct Answer
D:With this choice, the selected action reasons over supported network configuration to explain a path or blocking component; it does not generate live probe packets or test application response times, providing configuration-based network path diagnosis for the network described.
Incorrect Answers
A:Although this setting represents registered global network resources and their relationships, its topology view is not the same as a packet capture; this concerns aggregated WAN and TGW topology awareness, not the specified configuration-based network path diagnosis.
B:The proposed action evaluates service metrics against alerting conditions; CloudTrail management logs record API events rather than continuous circuit status metrics, supporting automated connectivity-state alarms but leaving configuration-based network path diagnosis unmet.
C:This approach emits request-level records with load-balancer fields for analysis; a network flow log cannot show HTTP URLs or status codes from the application layer, which helps with detailed application ingress request evidence instead of delivering configuration-based network path diagnosis.
Question 404
A compliance audit requires flow data retained centrally for a year with controlled account access. Which change is the most appropriate?
- Turn on VPC Flow Logs at the database ENI and retain ACCEPT/REJECT records
- Deliver VPC Flow Logs to a protected central S3 destination with retention controls
- Account for Flow Logs exclusions, aggregation intervals, and collection limitations
- Use Athena over a suitable Flow Logs dataset and aggregate by IP fields
Explanation
Correct Answer
B:This configuration archives flow records for long-term cross-account audit; local instance disks are not a reliable organization-wide log store, so it delivers durable governed network activity evidence under the stated constraints.
Incorrect Answers
A:This alternative records packet-flow metadata and network allow or reject disposition; application database logs will not see packets denied before arrival, so it addresses forensic visibility into database connection attempts rather than the required durable governed network activity evidence.
C:The proposed action treats absence of flow metadata as incomplete evidence rather than certainty; not all AWS-reserved traffic is recorded like an ordinary ENI flow, supporting defensible interpretation of VPC flow record gaps but leaving durable governed network activity evidence unmet.
D:This approach supports SQL analysis of archived network records; CloudTrail does not provide per-connection byte counts for data-plane network flows, which helps with historical large-scale flow anomaly investigation instead of delivering durable governed network activity evidence.
Question 405
An enterprise wants to prevent child accounts from disabling required network security logging APIs. Which change is the most appropriate?
- Use AWS Firewall Manager policies with appropriate organizational scope
- Share supported security and networking resources using AWS RAM under approved principals
- Deploy AWS Config rules or conformance packs for the network configuration
- Apply an appropriately scoped AWS Organizations service control policy
Explanation
Correct Answer
D:This configuration establishes organization-level maximum permissions for member accounts; an SCP limits permissions but does not enable a missing logging resource by itself, so it delivers organization-enforced restrictions on disabling controls under the stated constraints.
Incorrect Answers
A:This approach centrally manages eligible firewall protections for organization resources; creating one web ACL in the management account does not attach it to every account's ALBs, which helps with consistent multi-account WAF deployment governance instead of delivering organization-enforced restrictions on disabling controls.
B:This alternative distributes use of centrally owned network resources across accounts; RAM sharing is not a universal replacement for IAM resource authorization, so it addresses governed multi-account network resource access rather than the required organization-enforced restrictions on disabling controls.
C:Although this setting evaluates recorded resource configurations against defined compliance conditions, Config reports compliance rather than inherently blocking a change at the API call; this concerns continuous detection of noncompliant network rule changes, not the specified organization-enforced restrictions on disabling controls.
Question 406
An application must use WebSocket communication through an AWS managed load balancer. Which AWS networking approach meets this constraint?
- Create an ALB listener redirect action for the matching path
- Add an ALB query-string condition to a higher-priority listener rule
- Configure an ALB fixed-response listener action
- Place the WebSocket application behind an Application Load Balancer
Explanation
Correct Answer
D:The approach supports HTTP upgrade semantics for WebSocket connections; configure appropriate timeouts for expected idle periods rather than assuming normal short-lived requests, directly enabling long-lived HTTP-upgraded application sessions in this situation.
Incorrect Answers
A:Although this setting responds with a configured HTTP redirect to the client, a forward action would keep traffic on backend targets instead of informing the browser to navigate; this concerns client-visible URL redirection at layer 7, not the specified long-lived HTTP-upgraded application sessions.
B:The proposed action evaluates specified HTTP query parameters for request routing; Network Load Balancer listeners cannot inspect application query parameters, supporting parameter-driven routing within an HTTP listener but leaving long-lived HTTP-upgraded application sessions unmet.
C:This approach generates an HTTP status and optional response body at the load balancer; changing a DNS record does not provide an HTTP response body to the caller, which helps with immediate maintenance responses without invoking targets instead of delivering long-lived HTTP-upgraded application sessions.
Question 407
A backend needs TLS on both the client-to-ALB and ALB-to-target hops. What should the network specialist configure?
- Add a matching listener rule with a fixed deny response
- Use an HTTPS ALB listener and an HTTPS target group
- Configure an HTTP listener with a redirect to HTTPS
- Configure ALB authenticate-oidc listener actions
Explanation
Correct Answer
B:With this choice, the selected action terminates and initiates separate TLS sessions on each load-balancer hop; HTTPS to the load balancer does not automatically encrypt the backend leg, providing encryption on both sides of the ALB for the network described.
Incorrect Answers
A:This alternative evaluates HTTP headers and can return a configured HTTP status without forwarding; plain security group rules cannot examine HTTP header values, so it addresses header-based denial at the application ingress rather than the required encryption on both sides of the ALB.
C:The proposed action returns the redirect response that tells clients to use encrypted HTTPS; a backend TLS listener alone does not redirect a client that entered through HTTP, supporting enforced client-facing HTTPS navigation but leaving encryption on both sides of the ALB unmet.
D:This approach performs supported OpenID Connect authentication before forwarding requests; a network ACL cannot execute a web identity-provider sign-in flow, which helps with identity-aware access on the HTTP listener instead of delivering encryption on both sides of the ALB.
Question 408
A networking account has already attached many VPCs to one regional transit hub and wants a single VPN termination point. What is the best next configuration decision?
- Create a VPN attachment to AWS Transit Gateway
- Enable VGW route propagation in the relevant VPC route table
- Create a Site-to-Site VPN connection using the VPC's VGW as the target
- Associate regional TGWs with one DX gateway using a transit VIF
Explanation
Correct Answer
A:With this choice, the selected action terminates the managed VPN service at the shared routing hub; transit gateway route tables must grant each destination access deliberately, providing consolidated VPN access to selected VPC attachments for the network described.
Incorrect Answers
B:This alternative installs eligible propagated hybrid routes in a VPC route table; merely bringing up a BGP session is not enough when the subnet route table lacks a path, so it addresses learned routes from a virtual private gateway rather than the required consolidated VPN access to selected VPC attachments.
C:Although this setting terminates the AWS-side VPN tunnels at the virtual private gateway, a transit gateway is a different termination pattern with broader attachment routing; this concerns VPC-local hybrid VPN termination, not the specified consolidated VPN access to selected VPC attachments.
D:The proposed action links multiple regional transit routing domains to the on-premises circuit; allowed prefixes and ASN constraints need attention during association, supporting centralized hybrid routing across regional hubs but leaving consolidated VPN access to selected VPC attachments unmet.
Question 409
A TCP backend requires its own application to terminate TLS because the load balancer must not decrypt traffic. What is the best next configuration decision?
- Use an NLB TCP listener that passes the TLS bytes to the targets
- Configure the distribution's viewer HTTPS policy and a valid certificate
- Use an HTTPS target group with compatible target certificates
- Set the custom origin protocol policy to HTTPS Only
Explanation
Correct Answer
A:The approach forwards transport data without terminating the client's TLS session; an NLB TLS listener would terminate the client-facing TLS session at the load balancer, directly enabling backend-controlled TLS termination in this situation.
Incorrect Answers
B:This approach enforces TLS on the client-to-edge hop according to the selected policy; an HTTPS origin configuration alone does not secure the viewer hop, which helps with encrypted browser-to-CDN traffic instead of delivering backend-controlled TLS termination.
C:This alternative initiates TLS from the ALB to its backend targets; selecting an HTTPS listener protects only the client-facing leg, so it addresses protected ALB-to-target application hop rather than the required backend-controlled TLS termination.
D:Although this setting uses TLS when CloudFront establishes connections to the configured origin, viewer HTTPS does not automatically guarantee every origin fetch uses TLS; this concerns encrypted CDN-to-origin traffic, not the specified backend-controlled TLS termination.
Question 410
Network engineers need to apply a standardized route-table update safely to hundreds of accounts. Which change is the most appropriate?
- Use VPC-creation EventBridge events to invoke a Lambda policy-check workflow
- Route the matching CloudTrail event through EventBridge to a remediation target
- Send a CloudWatch alarm to SNS and the incident integration
- Orchestrate an approved automation workflow with Step Functions and scoped API operations
Explanation
Correct Answer
D:With this choice, the selected action coordinates retries, sequencing and error handling for network changes; a single manual CLI loop lacks workflow-state and recovery controls, providing repeatable multi-account route-management operations for the network described.
Incorrect Answers
A:This alternative reacts to new VPC creation events and runs focused automated network checks; a VPC-creation event filter does not detect subsequent security-group modification APIs, so it addresses event-driven VPC-creation governance rather than the required repeatable multi-account route-management operations.
B:Although this setting maps audited API activity to event-driven response logic, CloudWatch metrics do not by themselves reconstruct the API change request; this concerns near-real-time security-group change response, not the specified repeatable multi-account route-management operations.
C:The proposed action delivers notifications when the monitored threshold transitions state; a log delivery bucket alone does not send operational pages, supporting automated notification on connectivity failures but leaving repeatable multi-account route-management operations unmet.