Amazon AWS Certified Developer Associate Exam Prep
AWS Certified Developer - Associate DVA-C02 (Page 38 )

• Correct answer: B: Use a function alias with different versions.

• AWS Lambda versions are immutable. You publish a version for each code change.
• An alias is a movable pointer to a specific version (e.g., prod ? version 5).
• Deploying a new version is just publishing another version; directing production traffic to the new version is as simple as updating the alias.
• If you need to roll back, you re-point the alias to the previous version. This is minimal operational effort and avoids rebuilding pipelines or managing multiple deployment artifacts at runtime.

• A (blue/green with OpsWorks) adds complexity and tooling overhead.
• C (saving old deployment packages in S3) doesn’t provide runtime switching or instant rollback.
• D (CodePipeline) adds orchestration overhead; while useful, it’s more setup than the alias approach for simple rollback needs.

• Correct answers: IntegrationLatency and Latency.

• Why:

• Why not CacheHitCount/CacheMissCount: those relate to API Gateway caching. If you’re not using caching (or the problem isn’t caching-related), they won’t help diagnose a timeout.

• Practical tip: in CloudWatch, compare Latency and IntegrationLatency for the failing method/resource. If Latency is high but IntegrationLatency is low, the delay is outside the Lambda integration (gateway/network). If IntegrationLatency is high, the Lambda/backend is the bottleneck. Also review CloudWatch Logs for API Gateway and Lambda for additional clues.

• Why: Crisis management relies on established, repeatable procedures for responding to an incident (activation of the crisis team, escalation paths, communications, containment actions). This ensures a coordinated, timely, and auditable response.

• Why not the others:

• Correct answer: C: Amazon Comprehend.

• Why: The library wants to classify books based on their text content. This is an NLP (natural language processing) task. Amazon Comprehend is AWS’s managed NLP service that can perform content classification (including creating custom classifiers) and extract meaningful information from text. The other services are not focused on text classification:

• Quick note: In practice, you’d store the books in S3, extract text if needed (e.g., from PDFs with Textract), and then use Comprehend to classify the documents into topics or genres.

• Hardware and infrastructure
• System software
• Networks and communications
• Technology platforms and services

• Business Architecture: Defines business strategy, organization, functions, and processes.
• Data Architecture: Defines the structure and management of enterprise data.
• Application Architecture: Describes application systems and how they interact to support business and data processing.

• The user starts in the corporate portal.
• The portal launches the Salesforce resource.
• The IdP sends the SAML response to Salesforce.

• Connected App + OAuth is for OAuth authorization and API/app access, not this SAML-based seamless login scenario.
• SP-initiated SSO would begin when the user first requests the Salesforce resource and Salesforce redirects them to the IdP. That is not the described starting point.

• As the project progresses, you gain information, refine requirements, and lock down baselines (scope, schedule, cost). This reduces overall risk and uncertainty because more is known and addressed.
• At the same time, changes become more costly over time. Later changes can affect already approved baselines, cause rework, impact the critical path, require more coordination, and incur penalties or delays, all of which raise the cost of making changes.

• Network Security Groups (NSGs) control network traffic to and from Azure resources.
• By applying NSGs to the web tier and the database tier (subnets or NICs), you can:

• NSGs provide the necessary granularity (source/destination, port, protocol) to enforce the desired traffic patterns between tiers.
• For easier management you can use separate subnets for each tier or, optionally, use Application Security Groups to simplify rule management.

• Enable the owner dimension

• Assign a standard costing inventory model

• Batch dimension tracks batches or lots, such as expiration or production batches. It does not identify inventory ownership.
• Moving average is a costing method, but it is not the required choice for this consignment configuration.

• Answer: C – netstat -an

• netstat -an lists all active connections and listening ports with numeric addresses, without resolving names. This lets you spot DoS patterns such as a flood of connections to a specific port or many connections from a single or few IPs.
• The other options don’t help as directly:

• Windows: netstat -an and look for numerous ESTABLISHED connections to a service or many SYNs to a port.
• Filter by port, e.g., netstat -an | findstr :80, or on Linux: ss -tunap | grep ':80'.

• Netstat provides a snapshot. DoS detection often benefits from continuous monitoring, flow data, and IDS/IPS logs.

• Le rôle n’a pas de clés propres. Des identifiants temporaires (via STS) sont émis lorsque quelqu’un ou quelque chose « assume » le rôle.
• La trust policy déclare qui peut assumer le rôle (par ex. une instance EC2, un utilisateur IAM, ou un service comme Lambda).
• Une fois attaché à une ressource (par exemple comme un instance profile sur une EC2), l’application peut appeler les services AWS avec les permissions du rôle.

• Respect du principe du moindre privilège: on accorde uniquement ce qui est nécessaire.
• Pas de stockages de clés sur les instances; les credentials se renouvellent automatiquement.

• Rôles pour EC2, rôles pour Lambda, accès cross-compte, etc.

• The correct answer: B) Synthetic identity theft.

• Synthetic identity theft involves creating a new, forged identity by combining information from multiple real people (e.g., names, dates of birth, SSNs) to commit fraud.
• In the scenario, Adam “created a new identity by obtaining information from different victims,” which matches the idea of synthesizing data to form a fake person.

• Medical identity theft: using someone’s medical information to obtain care or services.
• Tax identity theft: using someone’s personal info to file fraudulent tax returns.
• Social identity theft: impersonating someone to deceive others socially or publicly.

• Look for phrases like “create a new identity” or “combine information from multiple people” to identify synthetic identity theft.

• Basic: Self-help only; no technical support or design assessment.
• Developer/Standard: Technical support, but generally not the full proactive architecture guidance required here.
• Professional Direct: Includes proactive guidance and architecture recommendations.
• Premier: Also supports this, but is not the minimum-cost option.

• Primary and core nodes: Use On-Demand Instances because the workload is business-critical. These nodes manage the cluster and store/process HDFS data.
• Task nodes: Use Spot Instances in an instance fleet. Task nodes are suitable for interruption because they do not hold essential cluster data and can be replaced or diversified across instance types.
• Terminate the entire cluster after processing: The job runs only about six hours each morning, and EMRFS stores data in Amazon S3. Keeping the cluster running for the rest of the day would waste money.

• A: Using Spot for primary and core nodes risks interruption of the critical cluster.
• C: All On-Demand is reliable but unnecessarily expensive; terminating the cluster helps, but Spot task nodes provide greater savings.
• D: Leaving primary and core nodes running after the task finishes continues to incur costs. Savings Plans also are less appropriate for this intermittent workload.

• Answer:

• Why:

• Why the other centers aren’t the right fit here:

• Alice is co-resident on the same physical host and exploits shared hardware (the processor cache) to infer secrets. This is the classic definition of a side-channel attack—information leakage through implementation details (like timing or cache behavior) rather than by breaking a protocol or injecting code.

• Observing cache timing or access patterns to deduce cryptographic keys or plaintext data from the victim VM.

• Man-in-the-cloud attack: targets cloud trust/auth, not local hardware sharing.
• SQL injection: exploits input to run SQL commands, not a VM/caching vector.
• Service hijacking: takes control of a service, not about covert data leakage via shared hardware.

• Notice phrases like “shared hardware resources,” “co-resident,” or “cache”—these indicate a side-channel vector.

1. Download the updated VPN client configuration package from the Azure VPN gateway.
2. Remove or update the existing VPN client configuration on the Windows 10 workstation.
3. Install the new package and reconnect.

• The correct option is A: Data architecture.

• Why: In the AWS CAF, the Platform perspective covers the technical foundation and architecture that enable cloud workloads to run reliably and efficiently. This includes how data is modeled, stored, and accessed across the enterprise—the core of data architecture.

• Quick mapping for the other options:

• A) configure matching hold and delay timers

• B) configure matching key-strings

• C) configure matching priority values

• D) configure unique virtual IP addresses

• administrators — Full access to switch configuration and REST API functions; excessive for this requirement.
• sysadmin — Intended for highly privileged system administration, not basic monitoring.
• helpdesk — More limited and focused on troubleshooting/support functions; it does not match the stated default role and level-1 requirement as directly.

• Why: Table.Profile returns a per-column profile that includes statistics such as count, null count, distinct count, and standard deviation. It also provides min/max and average where applicable, which matches the requested metrics (Count, Average, Null count, Distinct count, Standard deviation).
• Syntax: Table.Profile(table as table, optional additionalAggregates as nullable list) as table
• How it helps: After running Table.Profile on your table, you can extract the per-column stats you need and display them in your semantic model or report.

• MFA verifies a user’s identity using additional authentication factors, such as a phone prompt or security token.
• It helps prevent unauthorized access even if a password is compromised.
• It does not provide secure storage or encryption of credentials used during automated deployment.

• Workspace: Stores notebooks, libraries, jobs, and other project resources.
• Notebooks: Interactive documents containing code, queries, visualizations, and explanations. Common languages include Python, SQL, Scala, and R.
• Clusters: Groups of virtual machines that run Spark workloads. Clusters can be started, stopped, and automatically scaled.
• Data access: Databricks can read from services such as Azure Data Lake Storage, Azure Blob Storage, and Azure SQL.
• Jobs: Automate notebooks or data-processing workflows on a schedule or in response to events.

Why

cmd 
PowerShell.exe -ExecutionPolicy Bypass -File C:\Scripts\ConfigureVM.ps1

Why the other options are less suitable

• GPO logon script: Runs only when a user logs on and may not run during initial VM provisioning.
• GPO startup script: Can work, but requires the VM to be joined to the domain and the policy to be applied. It is also normally evaluated at each startup.
• Place scripts in a VHD: Merely placing scripts on a disk does not cause them to execute.

• Enable the owner dimension
• Allocate a standard costing inventory model

• Owner dimension (B): This dimension Lets you track who owns the stock. By enabling the owner dimension, items can be configured as either company owned or consignment (vendor-owned) when you create or edit items. Without enabling this dimension, you can’t designate ownership per item.
• Standard costing inventory model (D): Selecting a costing model determines how item costs are calculated and posted. Standard costing provides a fixed cost per unit, which is commonly used for agreed pricing scenarios like consignment arrangements for easier accounting and valuation. It helps ensure consistent cost treatment across transactions for items that can be owned by the company or on consignment.

• Batch dimension (A): Batch tracking is unrelated to ownership and isn’t required to support company-owned vs. consignment configurations.
• Moving average costing (C): This is an alternative costing method. It’s not required to enable ownership config, and the exam’s expected choice focuses on standard costing for this scenario.

• S3 Versioning stores all versions of an object. If an object is overwritten or deleted, you can recover the previous version using its version ID.
• This protects against accidental deletion or overwriting because the original data remains accessible as an older version.
• How to enable:

• Practical notes:

• S3 Lifecycle rules: automate moving/expiring data, not specifically protection against deletion.
• S3 bucket policies: control access but don’t inherently preserve previous data.
• S3 server-side encryption: protects data at rest, not against deletion/overwrite.

• The target API uses HTTPS, so Mule must validate the server’s TLS certificate.
• The TLS configuration is set to None, meaning no custom truststore is configured.
• Mule therefore uses the JRE’s default truststore to determine whether the target certificate is trusted.
• If the issuing CA certificate is in that truststore, the TLS handshake can succeed.
• If it is absent—or the certificate is otherwise invalid—the request fails with a TLS/handshake error.

• Amazon Cognito is designed for customer-facing apps to handle user sign-up, sign-in, and access control, and it can federate identities from social providers (Facebook, Google, etc.) or enterprise IdPs via SAML/OpenID Connect.
• You can configure a Cognito User Pool and connect social identity providers, then use tokens (JWT) to authorize backend API calls.

• AWS Directory Service is for connecting your AWS apps to an existing directory (like Active Directory) for enterprise users, not social login for customer apps.
• AWS IAM is for managing access to AWS resources, not end-user authentication for your website.
• AWS IAM Identity Center (AWS SSO) provides SSO for AWS accounts and enterprise apps, not typical social logins for consumer-facing websites.

• Multi-pass wipe: Overwrites the drive’s existing data multiple times, making recovery much more difficult while preserving the drive’s functionality.
• Single-pass wipe: May be sufficient in some modern sanitization standards, but is presented here as less secure than multiple overwrites.
• Degaussing: Uses a strong magnetic field to disrupt data. It can render the drive unusable or unreliable, reducing its resale value.
• Pinning: Is not an appropriate data-sanitization method.

• Context: You’ve enabled auditing in Dataverse and need to trim audit data to free storage. The question asks which deletion options you can use.

• What the options typically mean:

• About the provided answer (A, C, D): The list includes “by column,” which isn’t a typical or supported way to purge audit data. The more plausible trio is A (by record), B (date range), and C (by table older than date). If the exam expects A, C, D, that seems incorrect or mis-stated in the source.

• Practical takeaway: To reduce audit storage, use per-record deletions, per-table purge by date, and/or date-range deletions as supported by the environment’s audit management UI or admin docs.

• Correct answer: All four statements are true (A, B, C, and D). The given key (A,B) is likely incorrect.

• A) Customers can change the size of the Warehouse after creation — Yes. You can resize a virtual warehouse after it’s created using ALTER WAREHOUSE ... SET WAREHOUSE_SIZE.
• B) A Warehouse can be resized while running — Yes. Snowflake supports online resizing; you can change the size without stopping queries.
• C) A Warehouse can be configured to suspend after a period of inactivity — Yes. You can enable auto-suspend with a delay (AUTO_SUSPEND).
• D) A Warehouse can be configured to auto-resume when new queries are submitted — Yes. You can enable auto-resume (AUTO_RESUME) so a suspended warehouse automatically resumes on new queries.

• Example commands:

• Even if a warehouse is resizing or auto-suspending, queries will be queued and then executed once the warehouse has the appropriate capacity.

• AWS IoT Greengrass supports local ML inference using models trained in Amazon SageMaker.
• The model and inference code run on the factory’s local server, so processing continues even when internet connectivity is unavailable.
• A Greengrass component can:

• This provides low latency and avoids sending images to AWS for every inference.

• A: Uses AWS-hosted services and therefore depends on internet connectivity. It would fail during an outage.
• C: Snowball Edge is unnecessary for this use case and adds deployment complexity. A local Greengrass server is the intended edge-inference solution.
• D: Amazon Monitron is designed for monitoring industrial equipment health, not analyzing camera images with a custom SageMaker model.

• Looking up accounts, contacts, and opportunities
• Logging calls and updating Salesforce records
• Accessing previously available customer information when temporarily offline

• Salesforce Touch App: Primarily an older tablet-focused experience, not the best general solution for the sales team.
• Custom hybrid app: Unnecessary development when Salesforce provides the required capabilities natively.
• SalesforceA: Intended mainly for Salesforce administrators, not sales representatives.

• What it’s asking: In an ARM template, for an Availability Set, what value should you set for the property platformFaultDomainCount to maximize availability during fabric failures or maintenance?

• Key concept: Fault domains are groups of hardware that can fail independently. By spreading VMs across more fault domains, you reduce the risk that a single hardware fault takes out many VMs.

• Important detail: For managed Availability Sets, the number of fault domains you can use varies by region — typically 2 or 3.

• What to choose: Set platformFaultDomainCount to the maximum supported in your region. In most regions this is 3, which gives you the best resilience. If your region only supports 2, you’d use 2.

• Answer: 3 (Max Value). In ARM template syntax, this would appear as "platformFaultDomainCount": 3 (within the Availability Set resource).

• On-Demand: You pay by the hour with no long-term commitment. This is ideal for workloads that are infrequent or have highly variable usage. Since this job runs only 24 hours once per year, you pay only for those 24 hours, with no wasted upfront or long-term payments.
• Reserved Instances: Require a 1- or 3-year commitment and pay for capacity whether you use it or not. For a workload that runs just 24 hours a year, you’d be paying for most of the term unused, making it far less cost-efficient.
• Spot Instances: Can be interrupted whenever AWS needs capacity, which is unacceptable for an uninterruptible workload.
• Dedicated Instances: Generally more expensive and aimed at licensing or compliance requirements; not needed for this use case.

• Windows 10 VMs
• Windows Server 2012 or later VMs
• Running VMs—they do not need to be shut down
• Debian 8.2+ VMs, assuming the specific version is supported
• Stopped or deallocated VMs

• A: Daily involvement is unnecessary and may not solve the availability problem.
• C: Clarifying all requirements at the start conflicts with agile’s iterative refinement.
• D: Simply reviewing based on availability leaves the problem unresolved and allows rework to continue.

kusto 
Event 
| summarize make_set(EventID) by Computer

• summarize groups records.
• by Computer creates one result row per virtual machine.
• make_set(EventID) returns an array containing unique event IDs for that computer.

kusto 
| summarize make_list(EventID) by Computer

• Authenticating websites with TLS/HTTPS
• Enabling certificate-based VPN authentication
• Signing or encrypting email
• Supporting device or user authentication

• VLAN tagging: Uses network-frame tags, such as 802.1Q; it does not rely on X.509 certificates.
• LDAP: May integrate with PKI in some environments, but X.509 certificates are not most commonly associated with LDAP itself.
• MFA: Certificates can be one authentication factor, but X.509 is fundamentally a PKI technology.

• Uses on-premises data or resources
• Runs components in the cloud
• Can scale across multiple cloud environments when demand increases

• Public cloud: Resources are hosted entirely by a cloud provider.
• Private cloud: Resources are dedicated to one organization, usually in its own environment.
• Hybrid: Combines on-premises and cloud resources.

• Correct answer: D. AWS CloudShell

• Why: AWS CloudShell is a browser-based shell that runs in the AWS Console and uses the current authenticated session. It provides a pre-authenticated, ready-to-use command-line environment directly from the Management Console, with AWS CLI and common tools installed.

• Why the other options aren’t correct:

• Permanent table (E): Correct. A dropped permanent table can be restored with UNDROP TABLE during its Time Travel retention period. Permanent tables also have Fail-safe protection.
• Transient table: It can also generally be restored during its shorter Time Travel period, although it has no Fail-safe. Therefore, excluding it makes the question questionable.
• Temporary table: Usually cannot be recovered after it is dropped; its lifecycle is limited to the session.
• Materialized view (D): The answer key treats it as recoverable, but recovery behavior depends on the specific Snowflake object/version capabilities. It should not be confused with an ordinary view.

• Azure Cosmos DB is a globally distributed NoSQL database service. It stores and retrieves application data, but it does not provide the tools needed to build, test, and deploy predictive analytics models.
• Azure Machine Learning—including the historical Azure Machine Learning Studio—is designed for the machine-learning lifecycle:

• The Well-Architected Framework has five pillars: Operational Excellence, Security, Reliability, Performance Efficiency, and Cost Optimization.
• Operational Excellence: how you run and improve your systems—monitoring, incident response, and evolving processes.
• Reliability: the ability of a workload to recover from failures, maintain uptime, and scale as demand changes.

• Availability (A) is not a pillar name; it’s an outcome that relates to Reliability.
• Scalability (C) isn’t a pillar name; scalability touches on Performance Efficiency.
• Responsive design (D) is not a pillar in the Well-Architected Framework.

• Answer: A — EC2 Image Builder

• Why: EC2 Image Builder is AWS’s fully managed service designed to automate the creation, testing, and ongoing management of custom EC2 AMIs. It lets you build image pipelines that start from a base image, apply software/components, run tests, and publish/distribute the resulting AMIs across regions or accounts.

• How it works (high level):

• Why not the other options:

• Quick tip: Use EC2 Image Builder to reduce manual image maintenance and drift, and to enforce consistent, tested base images across environments.

• Product Owner: May attend, but is not required unless also working as a Developer.
• Scrum Master: May attend to help facilitate or coach, but is not required.
• Developers: Must participate because the event is specifically for them.

• Answer: Data enhancement.

• Why: Augmenting gold-layer tables with an additional dataset is enriching or enhancing the existing data to support the ad-hoc analysis. The other options don’t capture the idea of adding external data to improve the dataset (ad-hoc improvements = tweaks, last-mile dashboarding = building dashboards, last-mile ETL = ETL steps at the end of the pipeline). In practice, this is often also called data enrichment.

Why B works

• AWS KMS keys are Regional resources. A normal customer managed key in Region A cannot be used directly in Region B.
• A customer managed multi-Region KMS key (MRK) has related key replicas in both Regions. The replicas share key material and key ID, although each has a Regional ARN.
• With client-side encryption, the application encrypts the data before storing it in S3. Cross-Region replication then copies already-encrypted objects, so S3 does not need to decrypt and re-encrypt them with a different Regional key.

Why the other choices are weaker

• A and C: SSE-S3 uses Amazon-managed S3 keys, not the required customer managed KMS key.
• D: SSE-KMS can work only if the solution creates and configures the appropriate KMS key or multi-Region key replica in each Region. As written, it says to create a customer managed KMS key in each Region, which implies separate keys—not the same KMS key. Replication also requires additional KMS permissions and destination encryption configuration.