AWS Certified Solutions Architect - Associate SAA-C03 Practice Test 64
Question 630
An RDS Multi-AZ database is expected to fail over within an agreed outage window. The application has long-lived pooled connections and DNS caching. The database successfully promotes, but clients never reconnect without manual restarts. What should be tested and fixed?
- Increase the read replica count but leave clients pinned to stale writer connections.
- Exercise real database failover and verify client DNS refresh, connection retry/pool reset and transaction recovery behavior.
- Make the DNS cache TTL infinite so the application uses the original writer endpoint indefinitely.
- Disable database monitoring because Multi-AZ guarantees every connection remains uninterrupted.
Explanation
Correct Answer
B:DB promotion is only one step; applications must discover and establish valid sessions to the new writer endpoint.
Incorrect Answers
A:Extra readers do not repair application writer-reconnection logic.
C:Indefinite endpoint caching blocks timely adaptation when the writer changes.
D:Failover can drop active sessions and still needs application recovery logic and visibility.
Question 631
An audit report claims an application has an RTO of five minutes and RPO of zero based only on a database service's durability marketing statement. No full recovery exercise has been measured. What evidence should replace the claim?
- Use an S3 availability SLA as a direct numeric substitute for the application's RTO and RPO.
- Compute RTO by subtracting two EC2 instance sizes and report the result as minutes.
- Measure and record end-to-end application recovery elapsed time and actual data-loss window during realistic DR exercises.
- Declare an RPO of zero whenever CloudTrail logs are enabled in the account.
Explanation
Correct Answer
C:Durability percentages describe storage characteristics; observed RTO and RPO include restore/cutover steps and data replication lag.
Incorrect Answers
A:A service availability objective is not an end-to-end recovery time or recoverable-data freshness measure.
B:Instance sizing has no direct mathematical equivalence to outage duration.
D:Audit logging does not guarantee a lossless transactional replication mechanism.
Question 632
A DR drill exposed broken IAM roles in the standby Region and a missing customer-managed KMS key. The team fixes only the slide deck and leaves the real deployment unchanged. Which acceptance criterion is appropriate?
- Mark the exercise passed because the failure was observed, even though the standby environment still cannot decrypt data.
- Increase the disaster-recovery slide count and omit any new service API calls.
- Disable encrypted backups to make the scenario disappear rather than repair destination key permissions.
- Remediate the missing roles and key access, rerun recovery and verify the previously failing path before declaring readiness.
Explanation
Correct Answer
D:A failed real dependency remains an operational defect until corrected and re-tested; updating documentation cannot authorize the next recovery.
Incorrect Answers
A:Identifying a defect is valuable evidence but does not satisfy a recovery capability gate.
B:Additional documentation alone cannot supply working IAM/KMS access.
C:Removing the required protection sacrifices recoverability/security and does not provide a validated DR deployment.
Question 633
A customer-facing relational cache is backed by an EC2 EBS gp2 volume. Its random I/O demand is stable at 6,000 IOPS, and throughput occasionally requires separate tuning. The architect wants predictable performance without tying IOPS to volume size. What is the best EBS storage choice?
- Move to a suitably provisioned EBS gp3 SSD volume and set IOPS and throughput according to measured demand.
- Choose sc1 cold HDD as the primary volume because random I/O is best served by low-cost cold storage.
- Move production block I/O directly to S3 object PUT operations without adapting the application.
- Increase the gp2 volume's allocated GiB arbitrarily and assume the most economical capacity setting is reached.
Explanation
Correct Answer
A:gp3 decouples allocated storage capacity from provisioned IOPS and throughput within service and instance limits, unlike gp2 sizing-dependent behavior.
Incorrect Answers
B:sc1 is designed for infrequent sequential access and is a poor match for sustained small random I/O.
C:S3 has an object API, not a drop-in low-latency EC2 block-device interface.
D:Increasing gp2 size to reach performance targets adds storage cost and does not independently tune throughput.
Question 634
An EC2 video-rendering service uses gp3 and meets its IOPS target but reads large files at a capped MB/s rate. CloudWatch shows throughput saturation while average I/O operation size is large. Which adjustment should be considered?
- Raise provisioned gp3 IOPS only and assume bytes-per-second automatically rises regardless of throughput setting.
- Increase gp3 provisioned throughput, subject to volume and EC2 EBS bandwidth limits.
- Increase EBS snapshot retention and treat backup history as bandwidth provisioning.
- Replace the volume with cold HDD because it guarantees more random-read bandwidth than gp3 SSD.
Explanation
Correct Answer
B:Large sequential transfer can exhaust MiB/s before operation counts; gp3 offers separately configurable throughput.
Incorrect Answers
A:Increasing IOPS does not bypass an independently configured throughput ceiling.
C:Retention determines backup lifespan, not live EBS throughput.
D:Cold HDD is not a universal high-throughput replacement and has different latency/usage characteristics.
Question 635
A team provisions a gp3 volume for higher MB/s than the instance family can deliver over its EBS connection. Benchmarks stop improving despite increasing the volume setting. Which constraint must be included in capacity planning?
- Assume any EBS volume provisioned for high throughput forces the EC2 instance's EBS attachment to the same rate.
- Make the root account owner of the volume to raise instance bandwidth.
- Measure the attached instance's EBS-optimized bandwidth and IOPS ceilings as well as the volume's own settings.
- Enable VPC DNS hostnames to remove the instance-side EBS performance limit.
Explanation
Correct Answer
C:End-to-end disk performance is limited by the slowest supported link, including instance EBS network capacity.
Incorrect Answers
A:Volume settings cannot override hardware and instance-family ceilings.
B:IAM ownership and permissions do not change network bandwidth allotted to an instance.
D:VPC DNS resolution is unrelated to the EBS data-plane capacity of the instance.
Question 636
A database cluster runs on two supported Nitro-based EC2 instances in the same Availability Zone. The clustering software provides a cluster-aware file system and coordinated write fencing, but it requires both nodes to see the same low-latency block device rather than an NFS file share. The team wants a supported EBS volume attachment model for concurrent access. Which storage design meets the stated constraints?
- Attach one gp3 volume with normal EBS single-instance attachment to both nodes, because all EBS SSD volume types support simultaneous multi-host writes by default.
- Use EFS as an NFS mount and assert that it exposes the same raw block-device semantics required by the cluster software.
- Create two independent EBS snapshot copies, one per instance, and expect their data blocks and write ordering to stay synchronized automatically.
- Create a compatible io2 EBS Multi-Attach volume and attach it to both supported Nitro instances in the same AZ, using the existing cluster-aware filesystem and write-fencing controls.
Explanation
Correct Answer
D:EBS Multi-Attach supports attaching eligible io2 volumes to multiple Nitro EC2 instances in one AZ. Coordinated writes and a cluster-aware filesystem/fencing remain essential because ordinary filesystems do not make concurrent raw-block writers safe.
Incorrect Answers
A:Normal gp3 attachment does not provide EBS Multi-Attach. Multi-Attach is restricted to supported Provisioned IOPS SSD io1/io2 configurations, not arbitrary EBS SSD volumes.
B:EFS offers shared POSIX file access over NFS. It is not the same raw shared EBS block device required by this cluster and cannot transparently replace a block-level cluster storage design.
C:Snapshots produce independent point-in-time block copies; separate volumes do not share future writes or provide a synchronized clustered device.
Question 637
A design note claims every EC2 instance with any io2 EBS volume automatically receives the maximum io2 Block Express capabilities. A proposed instance family is not on the applicable support list. Which guidance is accurate?
- Check the specific instance and volume compatibility matrix before relying on Block Express performance claims.
- Ignore instance support because an io2 volume attaches to all instance families with identical Block Express behavior.
- Increase the io2 volume size and assume this enables all Block Express capabilities even though the attached instance family is unsupported.
- Enable the EBS volume's delete-on-termination flag as the mechanism for improving Block Express compatibility.
Explanation
Correct Answer
A:Advanced io2 performance and supported configurations depend on the attached EC2 and EBS combination.
Incorrect Answers
B:Attachability alone does not guarantee a particular advanced performance envelope.
C:Volume resizing does not alter the attached EC2 instance family’s supported Block Express path or bandwidth limits. Compatibility must be checked before promising performance.
D:Lifecycle deletion settings do not determine the supported high-performance EBS interface.
Question 638
A high-frequency trading application uses expensive provisioned-IOPS io2 storage. During a backup review, an engineer says those IOPS settings also guarantee point-in-time backup copies. What is missing?
- Keep raising IOPS until the volume inherently contains an immutable copy of every old record.
- Use tested EBS snapshot or application-consistent backup procedures in addition to the high-performance volume.
- Move only the EC2 instance to a larger subnet without configuring backup.
- Treat CloudWatch EBS volume metrics as a complete recoverable copy of the data.
Explanation
Correct Answer
B:io2 IOPS and durability describe the primary volume, not an independent historical restore point for accidental deletion or application corruption.
Incorrect Answers
A:Performance provisioning does not implement application history or data-version retention.
C:Subnet space is unrelated to preserving recoverable historical block data.
D:Operational time series record activity, not the volume's application blocks.
Question 639
A nightly ETL system streams multi-terabyte sequential scans from an attached block disk. The workload is not boot storage, tolerates HDD latency, and rarely performs small random I/O. Which EBS type is a natural fit to evaluate?
- Use sc1 solely because it guarantees the highest throughput under continuously busy streaming access.
- Use io2 provisioned-IOPS SSD without measuring whether low-latency small operations are valuable.
- Use throughput-optimized HDD EBS st1 with workload throughput benchmarks and appropriate sizing.
- Put the streaming dataset in CloudWatch Logs and mount it as an EBS block disk.
Explanation
Correct Answer
C:st1 is designed for large sequential throughput workloads rather than SSD-style small random operations.
Incorrect Answers
A:sc1 prioritizes low-cost infrequent access and has lower performance than st1 for frequently streaming data.
B:io2 can meet stringent latency but its higher-cost positioning is unnecessary for a tolerant sequential job.
D:CloudWatch Logs is a log ingest/query service, not a block volume suitable for streaming ETL scans.
Question 640
A compliance archive occasionally streams large sequential files for audit, perhaps once every few months. It requires an EC2-attached block device, but slow access is acceptable. Which EBS storage type merits cost-oriented evaluation?
- Use high-IOPS io2 SSD by default because every archive access requires transactional database latency.
- Change the data to S3 Intelligent-Tiering and expect EC2 to mount it as an unmodified EBS block volume.
- Use st1 exclusively because sc1 cannot hold user-created files at all.
- Use EBS sc1 cold HDD if its size, nonboot and performance constraints fit the archive workload.
Explanation
Correct Answer
D:sc1 favors inexpensive infrequent sequential block access when sustained performance is not the top priority.
Incorrect Answers
A:The workload is a rarely scanned archive, so provisioned transactional IOPS would add unnecessary cost.
B:S3 is object storage, not an EBS block-device volume with the same filesystem semantics.
C:sc1 is a block storage volume that can hold a filesystem; its differentiator is access/performance economics.