AWS Certified Solutions Architect - Associate SAA-C03 Practice Test 86
Question 850
A scientific consortium changes its S3 bucket to Requester Pays. A third-party tool now receives 403 responses even though the caller can read objects, because it does not send the required requester billing acknowledgment. What should be evaluated?
- Widen the object's public-read policy as a workaround for missing requester billing acknowledgment.
- Verify client/API support for requester acknowledgment, requester account eligibility and compatible access patterns.
- Increase S3 object versioning frequency to prevent requester-charge errors.
- Change storage to Glacier Deep Archive because archive restores automatically remove all Requester Pays client constraints.
Explanation
Correct Answer
B:Requester Pays requires the caller to acknowledge associated charges; not every tool or access method automatically does so.
Incorrect Answers
A:Public authorization does not replace the billing acknowledgment and may expose data.
C:Versioning is unrelated to the request payer header/API parameter.
D:Archive class selection does not fix required request-payer semantics.
Question 851
An internal mobile app anonymously downloads public educational materials. The team proposes S3 Requester Pays but users have no AWS account credentials to accept billing. What makes this a poor design?
- Enable Requester Pays and assume every unauthenticated phone automatically acquires an AWS billing account.
- Replace anonymous public distribution with permanent root credentials embedded in the app to pay on behalf of all users.
- Use a conventional owner-paid delivery model such as CloudFront while treating Requester Pays as unsuitable for anonymous public clients.
- Use S3 Glacier archive restore to make unauthenticated browsers pay charges without credentials.
Explanation
Correct Answer
C:Requester Pays requires eligible requester account and billing acknowledgment, not an anonymous browser UX.
Incorrect Answers
A:The mobile client cannot supply the required payer account context.
B:Root credentials in a distributed client create severe security risk and undermine intended billing separation.
D:Archive retrieval does not establish authenticated requester billing.
Question 852
A fleet has oversized gp2 SSD volumes solely to receive higher baseline IOPS, but actual stored bytes are much smaller and the required performance is moderate. Which migration can reduce EBS spend?
- Keep all gp2 volumes oversized indefinitely because gp3 cannot configure IOPS or throughput separately.
- Switch database boot drives to sc1 cold HDD solely from its advertised GiB price.
- Increase gp2 volume sizes again without evidence of higher capacity needs.
- Evaluate gp3 at right-sized capacity with independently provisioned IOPS/throughput matching measurements.
Explanation
Correct Answer
D:gp3 separates storage from performance, avoiding excess capacity purchased only to reach gp2 performance levels.
Incorrect Answers
A:Independent gp3 performance configuration is a primary design advantage.
B:sc1 is not a suitable supported boot volume or small random I/O tier.
C:Growing gp2 volumes can increase some provisioned performance allowances, but also expands billable capacity. If the application needs IOPS or throughput independently of size, gp3 right-sizing may be more economical than continued overprovisioning.
Question 853
An AWS account contains hundreds of unattached 500-GiB EBS volumes created by terminated test instances. No owner or retention review has occurred, but the monthly bill is growing. Which safe cost action fits?
- Inventory orphaned volumes, confirm ownership and recovery requirements, then delete those genuinely unneeded.
- Immediately delete every volume without checking whether any contains the sole recovery copy of important data.
- Apply a cost-allocation tag to the unattached volumes but leave all volume capacity allocated indefinitely without owner signoff for deletion.
- Change EBS resource tags to 'deleted' but leave the volumes physically allocated.
Explanation
Correct Answer
A:EBS allocated volume storage can remain billable after EC2 termination; careful cleanup removes unused resources without destroying required data.
Incorrect Answers
B:Deleting attached or detached EBS volumes without a dependency and backup check can permanently remove the only copy of production data. The savings process must inventory ownership, validate snapshots and classify stale resources before deletion.
C:Tags improve visibility and charge attribution but do not release EBS volume capacity or stop its billing. Once unused resources and recovery obligations are established, safe removal is the actual optimization.
D:Tags label resources and do not deallocate storage.
Question 854
A backup team wants to delete old EBS snapshots to reduce cost. Several snapshots form incremental chains and some retained AMIs reference snapshots. What should be verified?
- Assume every snapshot is a complete independent full-volume billable copy and delete randomly.
- Identify dependencies and required recovery points/AMI references, then use supported snapshot deletion semantics for unneeded snapshots.
- Delete the latest snapshot automatically because it always contains the least unique data.
- Change snapshot descriptions instead of actually evaluating stale retention and block charges.
Explanation
Correct Answer
B:EBS snapshots are incremental; deleting one does not necessarily release its entire apparent size, and retained dependent blocks may remain needed.
Incorrect Answers
A:Incremental storage and referenced block retention make simplistic size accounting misleading.
C:There is no such universal ordering guarantee for required restore coverage.
D:Renaming or changing descriptions of EBS snapshots does not discard retained snapshot data blocks or stop their storage charges. Actual savings require retention decisions and deletion of unneeded recovery points while preserving required backups.
Question 855
An EBS io2 volume is configured for high provisioned IOPS and throughput, but CloudWatch shows it has used under 10% of either capacity for months. The application latency SLO is consistently met. Which cost review is appropriate?
- Keep maximum IOPS forever because provisioned performance charges disappear whenever a volume is idle.
- Increase both IOPS and throughput further to reduce the monthly volume price.
- Right-size provisioned storage performance to measured peak demand with headroom and benchmark the new configuration.
- Change VPC CIDR size as a way to discount the same provisioned EBS volume.
Explanation
Correct Answer
C:Provisioned performance carries cost even when unused, so measured utilization can reveal safe reductions.
Incorrect Answers
A:Capacity-based/provisioned performance billing does not automatically become free at low utilization.
B:Higher provisioned performance usually adds charges rather than lowering them.
D:Network address space does not control EBS performance pricing.
Question 856
A disaster-recovery team enables EBS Fast Snapshot Restore on 12 old recovery snapshots across multiple Availability Zones and leaves it enabled for months. The application now restores them only in occasional drills, and initial block-read latency is tolerable. What is the most direct ongoing cost correction?
- Delete the current production EBS volumes to stop the Fast Snapshot Restore fee while retaining the snapshots.
- Increase provisioned volume IOPS so existing FSR snapshot-AZ charges convert to no-cost storage credits.
- Enable FSR for all available snapshots in every AZ to share one account-wide billing clock.
- Disable FSR for unneeded snapshot/AZ combinations after documenting the restore tradeoff; enable selectively for drills or critical restore points.
Explanation
Correct Answer
D:FSR charges accrue while enabled per snapshot/AZ pair with a minimum billed period. Selectively disabling it removes ongoing enablement cost when its initialization benefit is not needed.
Incorrect Answers
A:FSR is charged for each enabled snapshot/AZ pair, not for the live production volume simply existing; deleting live volumes is destructive and unrelated.
B:Volume provisioned performance is billed independently and does not remove per-minute FSR enablement charges.
C:Each snapshot-AZ pair incurs its own enabled-period charges, so broadening coverage increases recurring cost.
Question 857
A cost program wants to replace every SSD volume with the cheapest HDD EBS type, including boot disks and a transactional MySQL writer. Why is a blanket replacement invalid?
- Retain supported SSD boot and small-random-I/O volumes; use HDD EBS only where workload and eligibility permit.
- Use sc1 as the root boot volume on every EC2 machine and assume no EBS boot-type restrictions.
- Move a random-I/O database to st1 without measuring latency or operation patterns.
- Choose HDD solely by lower $/GiB while ignoring required performance and unsupported volume cases.
Explanation
Correct Answer
A:HDD types have boot restrictions and are tuned for sequential I/O, not general low-latency transaction workloads.
Incorrect Answers
B:Cold HDD is not supported for that boot use case.
C:Sequential throughput does not equal transactional random IOPS.
D:An invalid or unusably slow design is not a cost optimization.
Question 858
Two proposed EBS configurations advertise different storage prices per GiB. The cheaper class requires much greater allocated capacity and cannot meet the needed throughput without a bigger EC2 host. Which comparison is valid?
- Choose the lower per-GiB number even if it causes unacceptable latency and requires three times the disk size.
- Compare total required provisioned GiB, IOPS/throughput, host bandwidth and performance SLO cost rather than unit storage price alone.
- Ignore EC2 instance EBS bandwidth because the volume alone determines achievable performance.
- Use the AWS account's IAM user count as the sole measure of EBS effective price.
Explanation
Correct Answer
B:Real expense includes capacity and performance required to make the application work, not just a single quoted storage rate.
Incorrect Answers
A:Unit price cannot replace total-cost and service-level analysis.
C:Host attachment limits can constrain the delivered I/O rate.
D:Identity inventory is unrelated to volume capacity and performance charges.
Question 859
A regional EFS filesystem stores 12 million historical tiny XML receipt files, averaging 6 KiB each, that are accessed only a few times per year. An engineer proposes moving all of them to EFS Infrequent Access using lifecycle policies, estimating the lower-cost tier solely from the 6 KiB logical size of each file. Which cost consideration must be included before approving the transition?
- Each EFS IA file is charged exactly its 6 KiB logical data size without minimums, so object-count economics can be ignored.
- Assume EFS IA meters each small-file payload in 4 KiB increments without any 128 KiB per-file minimum or separate Standard metadata charge.
- EFS IA has a 128 KiB minimum billable size per file even for smaller eligible files, while associated metadata remains billed in Standard and data access can incur additional charges; model the count and access before tiering.
- Enabling EFS One Zone automatically changes the billing minimum for these tiny IA files to zero without changing durability characteristics.
Explanation
Correct Answer
C:EFS IA and Archive meter small-file data with a 128 KiB billable minimum per file and keep file metadata in Standard. For 12 million very small files, the billable minimum can far exceed logical bytes. Evaluate access charges, sizing and alternate approaches before committing.
Incorrect Answers
A:Small files can tier under eligible lifecycle configurations, but EFS IA billing rounds each file up to a 128 KiB minimum for storage. Per-file overhead matters greatly across millions of tiny objects.
B:EFS IA data is metered in 4 KiB increments, but the storage class still imposes a 128 KiB minimum charge per small file and bills file metadata in Standard. Omitting those terms substantially understates cost across millions of tiny files.
D:EFS One Zone changes fault-domain and price characteristics but does not waive the per-file 128 KiB IA minimum. Regional durability requirements remain an independent design constraint.
Question 860
A frequently accessed EFS dataset generates high sustained read/write throughput. A cost proposal moves it to the cheapest tier without checking throughput or request charges, and users already see throttling. What should be measured?
- Compare only stored GiB and treat throughput as universally unlimited and free.
- Reduce file permission checks as the sole mechanism to obtain a lower EFS throughput rate.
- Turn off file system metrics so the proposed tier appears underused.
- Benchmark EFS throughput mode and selected storage/performance pricing under the actual high-throughput workload.
Explanation
Correct Answer
D:EFS performance and billing differ by mode and access tier; a low storage rate can be overwhelmed by throughput needs.
Incorrect Answers
A:Measured throttling already contradicts the assumption of unlimited I/O.
B:Security controls are not a replacement for provisioning a workable filesystem throughput model.
C:Missing telemetry does not establish actual performance or price viability.
