Amazon AWS DevOps Engineer Professional Exam Prep
AWS DevOps Engineer - Professional (DOP-C02) (Page 9 )

• RPO and RTO definitions:

• Why B and D meet these goals:

• How they complement each other:

• Quick tips:

• ??? AWS CloudFormation ?????? Lambda ???? ???? ??????????? API Gateway ???? ???? ??? ?????????? ???? ???? ????.
• ???????? ????? Lambda ??????? aimmutable ????, ???????? ???? ??? ???? ?????????? ???? ??????? (versions) ????? ????.
• Canary release strategy ?????? ???? ?????? ???????????????? ??????? ??????? ?????? new ??????????? ????? ????, ???????? ???? ???????? ???? ????.
• ??? ????????? ?????????????? ?????????? ???? Lambda ??? ??? API ???? ???? ???????? ???????? ???? ???? ????, ???????? ???? ??????????????? IaC ???????? ????? ????.
• ???????? ????? ??????????, canary ????? ????? ??????? ???????? 100% ?? ???? ???? (promote).

• A: Route 53 failover ?? ???? canary ???? ?????????, gradual traffic shifting ???? ????? ????; ?????? ?????? ???????? DR ????.
• C, D: Elastic Beanstalk ????? OpsWorks ?? serverless-????? ? ??? ??????? ???????????? ???? ?????.

• Correct answer: D – Do not enable default administrative accounts to ensure accountability.

• A – Do not use encryption methods … backups and sensitive information: Encryption helps protect data; not using it increases risk, not reduces insider threats.
• B – Do not allow administrators to use unique accounts during installation: We actually want unique admin accounts, not the opposite.
• C – Do not control the access to administrators and privileged users: Failing to control access directly enables misuse.

• 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.

• Leadership and stakeholder commitment
• Business capability and skills
• Organizational culture
• Availability of resources
• Ability to manage and sustain change
• Impact of the proposed transformation

• How ready the organization is
• Which areas require urgent attention
• How difficult each issue may be to resolve
• Risks that could affect implementation

• A: Places the assessment in Phase B and refers vaguely to creating views; this is not the prescribed technique.
• B: An Implementation Factor Assessment and Deduction Matrix is not the primary TOGAF technique described for business transformation readiness.
• D: A Business Scenario helps identify requirements and stakeholder concerns, but it is not the main technique for assessing organizational readiness.

• A? ??? Aurora Replicas? ?? ??? ???? ?? ???, ?? ???? Network Load Balancer(NLB)? ??????. NLB? ?? 4 ?? ???? HTTP ??? ?? ???(Sticky sessions)? ????? ???? ????.
• ??? ?? ??????? ?? ?? ???? ??? ???? ?? ????? ????? ?? ?? ???(?? ?/??? ??)? ?????. ? ??? ALB?? ?? ????, NLB?? ???? ?????.
• ??? ??? ??? ??? ???? ?? ???? ???? HTTP ???? ??? ALB? ???? ???. A? ? ??? ??????.

• A) MTU mismatch: OSPF neighbors must exchange Hello packets with a compatible MTU. If MTUs differ, the neighbor conversation fails and the adjacency cannot become Full.

• B) Incorrect subnet mask: Routers must be in the same IP subnet on the connected link to form a neighbor relationship. A subnet mismatch prevents Hello packets from being considered valid on the same network.

• D) Area ID not the same: Neighbors must share the same Area ID. A mismatch stops adjacency from forming beyond the 2-Way state.

• E) Different metric set on each end of the link: Cost differences do not prevent OSPF adjacency; they affect routing decisions, not neighbor formation.
• F) Router ID not defined: OSPF can auto-choose a router ID; an undefined ID is not a prerequisite for adjacency to reach Full.

kusto 
Event | where EventType == "error"

• == is the KQL equality operator.
• -eq is a PowerShell operator, not KQL.
• is is not the correct equality operator in this context.

text 
Event | where EventType –eq "error"

• Event | search "error" — valid, broad search.
• search in (Event) "error" — valid, broad search.
• Event | where EventType == "error" — valid, targeted filter.

• TCP is connection-oriented. It establishes a connection before data transfer using a three-way handshake (SYN, SYN-ACK, ACK), enabling reliable delivery, ordering, and flow control.

• UDP is connectionless. It sends datagrams without a prior connection and provides no guarantee of delivery, order, or protection against duplicates; any reliability is up to the application.

• B incorrectly states UDP uses acknowledgment packets; UDP has no built-in ACKs.
• C wrongly claims UDP provides reliable transfer and that TCP is connectionless.
• D misstates framing bits; neither protocol uses the listed TCP/UDP handshake bits in frames.

• Correct answer: C) After installing ES on the search head(s) and running the distributed configuration management tool.

• ES requires the Splunk_TA_ForIndexes.spl add-on on indexers to apply index-time configurations. It should be deployed via the distributed configuration management (DCM) flow after ES is installed on the search heads, so the indexers receive the proper configuration in a controlled, versioned bundle.

• A) Deploying when adding apps to the deployment server isn’t the ES-specific order; it bypasses the ES-instantiated workflow.
• B) Installing Splunk_TA_ForIndexes.spl first isn’t the recommended order; ES needs to be installed on the search heads first.
• D) It isn’t limited to indexer cluster sites or cluster master commands; the standard flow uses DCM to push the TA to indexers in general.

• Used for communication on the local link or LAN segment
• Automatically generated on IPv6-enabled interfaces
• Not routed by routers to other networks
• Commonly used by devices to communicate with their local IPv6 router
• Begins with FE80 through FEBF

• FC00::/7 — unique local unicast
• FE80::/10 — link-local unicast
• FF00::/8 — multicast
• 2000::/3 — global unicast

• 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.

• Correct answer: only new data added to the eventhouse (option E).
• Why: When you enable OneLake availability for the eventhouse, OneLake starts syncing data going forward. It does not automatically backfill or copy over data that already exists in the eventhouse before the enablement.
• What that means in practice: Any data added to the eventhouse after you enable OneLake will appear in OneLake (and be visible from OneLake file explorer). Pre-existing data in the eventhouse stays there unless you perform a separate backfill/copy operation outside the standard OneLake enablement.
• How to verify: add a small new dataset to the eventhouse after enabling OneLake availability, then check OneLake to confirm the new dataset appears.

• Create a record-triggered Flow on Opportunity.
• Run it when the record is created or updated.
• Add entry criteria such as Probability > 50%.
• Use Create Records to create the related Sales Demo Request, populating its Opportunity lookup.

• Apex Trigger: Possible, but unnecessary custom code for a straightforward automation requirement.
• Workflow Rule: Cannot create a related custom record.
• Process Builder: Could create a record, but Flow is Salesforce’s preferred and more capable declarative automation tool.

• A limited lifetime
• Permissions defined by an IAM role or policy
• The ability to access AWS APIs without using long-term IAM user credentials

• Amazon API Gateway — Builds and manages APIs; it does not generally issue AWS credentials for applications.
• IAM users — Usually use long-term credentials, which are less suitable for applications.
• IAM instance profiles — Provide temporary role credentials to applications running on EC2 instances, but are specifically tied to EC2. The broader requirement described is best met by AWS STS.

• Disabling GPS: Affects location services, not email connectivity.
• Configuring 4G usage only: Does not enable international data access and could prevent connectivity if 4G is unavailable.
• Connecting using a hotspot: Could provide data, but it is not the most direct solution and depends on another network or device.

• B. Enable column profile — This turns on column profiling, which computes statistics like min and max for each column.
• C. Show column profile in details pane — This ensures the per-column profile is visible in the details pane.
• E. Enable details pane — This makes the details pane available so you can view the column profile there.

• A. Show column value distribution may help with distribution but isn’t specifically about min/max.
• D. Show column quality details shows data quality (valid/null counts), not min/max.

• A: Security groups do not control traffic to an S3 gateway endpoint in this way. Gateway endpoints are configured through route tables.
• B: An S3 bucket policy may be needed for authorization, but the error specifically indicates a connectivity or endpoint-routing problem.
• C: Glue connection settings do not require a fully qualified domain name to resolve this endpoint issue.

• Quick context: In a three-tier network (Access, Distribution, Core), roles are:

• Why A is correct: The Distribution layer runs Layer 2 and Layer 3 technologies. It often handles VLAN access (L2) and can perform inter-VLAN routing or connect to the core (L3). So it makes sense for the distribution layer to support both L2 and L3.

• Why B is correct: The Core layer is designed to maintain continuous connectivity when devices fail. It is built for high availability and redundancy, providing multiple paths so the network remains reachable even if some components fail.

• Why the others are not correct:

• What wipe does: A factory reset that erases all data, apps, and settings and returns the device to the OOBE. It removes the device from management and resets identity.
• Why not for this scenario: The goal is to repurpose the same device to a new user with Autopilot. Autopilot Reset keeps the device’s Azure AD/Intune identity and re-provisions the device for the next user without a full wipe.
• What Autopilot Reset does: Removes user data and apps but preserves device identity and management connection, then reapplies the Autopilot provisioning for the next user.
• When you’d use wipe instead: If you’re selling or permanently discarding the device, or you truly want to scrub all traces and start fresh without re-enrolling.

• The problem describes the class updating field-level security on some profiles. To prevent updating fields that are not updateable for the current user, you should check each field’s updateability before making changes. Use DescribeFieldResult.isUpdateable() (e.g., via Field.describe() on each field) to guard updates.

• A and D (With Sharing): Running a class with Sharing affects record visibility, not whether a field can be updated by a user. It doesn’t prevent updates to fields the user shouldn’t modify.
• C (WITH SECURITY_ENFORCED in SOQL): This enforces FLS/FRC during queries, but it doesn’t control whether the Apex code updates fields or modifies permissions. It’s not addressing the update behavior directly.

• Why: ADS is designed to collect information about on-premises environments to plan migrations. It inventories details like hostname, IP address, MAC address, OS, hardware, and installed software, plus dependency mappings. This data helps you understand your current environment before moving to AWS.

• How it differs from the other options:

• Practical use: Install the ADS agent on on-prem hosts to collect data, then view the inventory in Migration Hub to inform migration planning and sequencing.

• Global Unicast: These are the IPv6 addresses that are globally routable on the Internet. They’re allocated by Regional Internet Registries (RIRs) and can be reached from anywhere with proper routing (similar to IPv4 public addresses). Example ranges include 2000::/3.

• Link-local: fe80::/10. Used only on the local link; not routable beyond the directly connected network.

• Unique Local Addresses (ULA): fc00::/7. Private addresses for internal use within an organization; not publicly routable on the Internet (like IPv4 private addresses).

• Multicast: ff00::/8. One-to-many addresses used for group communication, not unicast routing.

• Domeny tworza restrykcjony razem z typem. Wykorzystujesz je w kolumnach, aby miec spójna walidacje danych w wielu miejscach.
• To nie jest pelny niestandardowy typ z wlasnym input/output funkcjonowaniem. Aby stworzyc typ z wlasnym I/O i operacjami, uzylbys CREATE TYPE (lub rozszerzen w C). Domeny to uproszczona forma ograniczen na istniejacy typ.

• CREATE DOMAIN positive_int AS integer NOT NULL CHECK (VALUE > 0);
• CREATE TABLE orders (id serial, qty positive_int);

• latwo wymuszaja wspólne reguly dla wielu kolumn/naglówków,
• zmiana regul w jednym miejscu (domena) automatycznie wplywa na wszystkie kolumny ja uzywajace.

• 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.

• Co to znaczy: transakcje zachowuja sie tak, jakby byly wykonywane jeden po drugim. Dzieki temu nie ma brudnych odczytów, niepowtarzalnych odczytów ani phantom reads.

• Implementacja: PostgreSQL uzywa SSI (Serializable Snapshot Isolation). W praktyce oznacza to, ze jesli wykryje konflikt miedzy transakcjami, jedna z nich zostanie zakonczona bledem “serialization failure” i trzeba ja ponowic.

• Zalózmy tabele orders(customer_id int, amount int).

• Transakcja T1:

• Transakcja T2, równoczesnie:

• T1 ponownie wykonuje to zapytanie:

• Correct answer: A) Hashing

• Why: Hashing produces a fixed-size digest of the software. If the final build is altered in any way, the hash will change, enabling you to detect tampering by comparing the stored digest with a freshly computed one.

• Why not the others:

• Equipment and hardware
• Facilities
• Inventory
• Backup media
• Supplies stored at an alternate or remote location

• Personal belongings of staff: Usually not organizational assets.
• DR line-item revenues: Revenue is a financial impact, not a physical asset.
• Cloud-based applications: These are primarily logical or information-processing assets, even though they depend on physical infrastructure.

• Reusing features across different models and teams
• Consistent feature definitions
• Managing feature versions and metadata
• Using features for both training and inference

• SageMaker Data Wrangler: Prepares and transforms data; it is not primarily a shared feature repository.
• SageMaker Clarify: Helps detect bias and explain model predictions.
• SageMaker Model Cards: Documents models, including intended use, risks, and evaluation results.

• Correct answer: Day 3 (Option B)

• Why: In Engagement Studio, when the program is paused, the prospects’ wait times are also paused and do not count down. They resume from the same point when the program restarts. Here, the prospect was at day 3 of a 5-day wait when paused, so they resume on day 3 after the 1-day pause.

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.

• 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.

• Event | search "error"
• Event | where EventType == "error"
• search in (Event) "error"

• Recovery procedures actually work
• Recovery time and recovery point objectives can be met
• Staff understand their responsibilities
• Contact details, dependencies, and technical configurations are accurate
• Gaps or conflicts exist in the plan

• Not version-controlled: Creates a risk of using an outdated copy, but the plan might still be effective.
• Contact information needs updating: This is a specific weakness that can be corrected, often identified during testing.
• Not approved by senior management: Approval is important for authority and resource commitment, but an untested plan presents the most direct risk that recovery will fail when needed.

• Which Security policy matches
• Which NAT rule/translation is selected
• Which PBF rule applies
• Which route is used

text 
test security-policy-match ... 
test nat-policy-match ... 
test pbf-policy-match ... 
test routing fib-lookup ...

• Multiple nodes: Data is replicated several times in the primary region.
• Separate geography: A copy is asynchronously replicated to a secondary Azure region.
• Readable secondary: RA-GRS provides read-only access to the secondary replica, even when the primary region is available.

• GRS: Replicates to another region but the secondary copy isn’t normally readable.
• ZRS: Replicates across availability zones in the same region, not a separate geographic region.
• LRS: Keeps replicas within a single datacenter or region and provides no geographic redundancy.

• Answer: B — Improve employee training and awareness

• Why this is correct:

• Why the other options are less effective here:

• Quick practical note:

• The correct answer is “Think and work holistically” (Option B).

• Focus on value: ensures outcomes matter to stakeholders, but isn’t specifically about end-to-end delivery.
• Optimize and automate: about efficiency and performance, not the holistic view.
• Collaborate and promote visibility: about teamwork and sharing information, not the end-to-end scope.

• Use a field on Account to show the aggregated yearly shipments (a Roll-Up Summary).
• A Master-Detail relationship between Shipment and Account is required for Roll-Up Summary to work (and to ensure access is governed by the parent Account).
• OWD and the relationship type determine what users can see. If you want to restrict shipment-level access while still showing a summary on Account, Private OWD on Shipment plus Master-Detail helps, because access to shipments is controlled by the Account record.

• A (Public OWD on Shipment with Process Builder and a Lookup to Account): Not ideal. Public access would expose shipments broadly, and a lookup cannot support a built-in roll-up summary.
• B (Private OWD on Shipment, Roll-Up Summary, Master-Detail to Account): Best answer. Private shipments, but because of Master-Detail, access and the roll-up are tied to the Account. The Account can show the yearly total via a Roll-Up Summary field.
• C (Controlled by Parent on Shipment, Trigger, Master-Detail): Master-Detail is correct, but using a trigger is unnecessary for a straightforward roll-up; roll-ups are the standard, maintainable solution.
• D (Private OWD on Shipment, Trigger, Lookup to Account): More complex and not as efficient; no automatic roll-up, and lookup breaks the ease of summarizing by Account.

• The correct answer: C. Tokenization

• Why:

• Why the others are weaker:

• 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.

• Admin access to the deployment pipeline (B) – lets the developers use the pipeline and deploy content.
• Contributor access to the Development and Test workspaces (E) – required to deploy items into those workspaces.
• Viewer access to the Production workspace (D) – lets them view Production content without allowing deployment or modification.

• Contributor access to Production (F), because that could allow changes or deployment there.
• Viewer access to Development/Test (C), because Viewer is insufficient for deployment.
• Build permission to Production semantic models (A), because building reports on a semantic model is not required merely to view Production items.

• Basic: billing/subscription support only; no technical support requests can be opened.
• Developer, Standard, Professional Direct, and Premier: include technical support and allow opening new support requests.

• If option A corresponds to “Developer, Standard, Professional Direct, Premier,” that is the correct choice.
• If the option text is really “Premier only,” that would be incorrect per current Azure docs.

• A. Configure prompt modifications to enforce tone, disclaimers, and refusal behavior at the system level.

• D. Configure Power Platform DLP policies to restrict unauthorized data connectors.

• B: Manual topic-by-topic disclaimer edits are specifically discouraged.
• C: Channel settings do not replace agent-level Responsible AI controls.
• E: Publishing before enabling safety filters violates the stated deployment sequence. Responsible AI filters should be enabled before publication, not afterward.

• 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.

• 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.

• 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.

• runParallel is defined as async, so it returns a Promise.
• To use the result, you attach a then handler (or use await inside another async function).

• A: “Async runParallel() .then(data);” is invalid. “async” is a keyword for function declarations, not something you put in front of a call, and you’d need a function as the then-argument.
• B: “runParallel().done(function(data){return data;});” .done is not standard in native Promises (it exists in some libraries). Without a compatible library, this won’t work.
• C: “runParallel().then(data);” is invalid because then expects a function as its argument; data is not a function.
• D: “runParallel().then(function(data){ return data; });” is valid (or equivalently, runParallel().then(data => data);).

• The robust, standard option is D.
• B could work only with a library that provides .done; otherwise it’s not reliable.

• The app on EC2 connects to Aurora using DB credentials stored on the instance. Secrets Manager centralizes these credentials and can rotate them automatically, eliminating manual updates on each EC2 host.
• Automatic rotation reduces operational overhead and enhances security because credentials are rotated on a schedule without code changes.
• The app can retrieve the current secret at runtime (e.g., via the AWS SDK) and use it to authenticate to Aurora, avoiding reliance on locally stored files.

• B (Parameter Store) can store secrets but lacks seamless built-in rotation for database credentials like Secrets Manager; rotation often requires more custom work.
• C (S3) would require complex tooling to rotate and securely fetch credentials and still risks exposure if access policies aren’t perfect.
• D (Encrypted EBS volumes) would store credentials locally on each instance and does not automate rotation or centralized management.

Flat organisation

• Few levels of management
• A wide span of control—managers supervise many employees
• Shorter communication channels
• More employee autonomy and quicker decisions
• Fewer formal promotion levels

Tall organisation

• Many levels of management
• A narrow span of control—managers supervise relatively few employees
• A clear hierarchy and reporting structure
• More formal supervision and communication channels
• More obvious promotion and career stages