Huawei H12-891 Exam Prep
HCIE-Datacom V1.0 (Page 62 )

• Matching hashes: The software is unchanged.
• Different hashes: The software was modified or corrupted.

• Encryption: Protects confidentiality.
• Baselines: Define approved configurations or normal performance.
• Tokenization: Replaces sensitive data with tokens.

• Matching hashes suggest the file has not changed.
• Different hashes indicate that the file was modified, whether authorized or unauthorized.

• Backup: Helps recover the previous version but does not identify or stop unauthorized changes.
• File labels: Classify or mark files; they do not verify integrity.
• Security audit: May discover weaknesses or improper changes, but is periodic and not a direct technical integrity control.

• How quickly the vendor must respond to an incident or request
• Target resolution times
• Availability or uptime requirements
• Performance metrics and penalties for not meeting them

• SOW (Statement of Work): Describes the project’s scope, tasks, deliverables, and timeline.
• MOA (Memorandum of Agreement): Documents a formal agreement to cooperate or perform specific activities.
• MOU (Memorandum of Understanding): Records a mutual understanding or intent, often less binding than a contract.

• Portfolio definition cycle — establishes and maintains the portfolio strategy, objectives, and management framework.
• Portfolio delivery cycle — coordinates and monitors the delivery of change initiatives, ensuring the portfolio remains aligned with strategic objectives and delivers value.

• Practice — a structured area of portfolio management activity, such as risk management or resource management.
• Technique — a method used to perform an activity; it is not the term for portfolio delivery itself.
• Principle — a guiding rule for effective portfolio management.

• Leaf switches provide access ports for servers, users, and other devices.
• Spine switches provide the backbone between leaf switches.
• Every leaf switch connects to every spine switch, creating a predictable, full-mesh fabric between the two layers.
• Leaf switches do not connect directly to other leaf switches, and spine switches do not connect directly to other spine switches.

• A: Adding both a spine and leaf is unnecessary for simply adding access ports.
• B: It focuses on uplink speed, not the scalable topology.
• D: A single spine connection creates a bottleneck and a single point of failure.

• Accept: Acknowledging the risk without taking additional action.
• Transfer: Shifting the risk’s impact to a third party, such as through insurance or outsourcing.
• Mitigate: Reducing the likelihood or impact of the risk through security controls.
• Avoid: Eliminating the activity or process that creates the risk.

• Tokenization: Replaces the value with a nonsensitive token, often reversible through a secure token vault.
• Hashing: Converts data into a one-way fixed-length value, generally used for integrity checks or password storage.
• Obfuscation: A broad term for making data difficult to understand; it is less precise than masking in this context.

• R-squared: Typically used for regression, not classification.
• RMSE: Measures prediction error for continuous numerical values, so it is not the best fit here.
• Learning rate: A training hyperparameter that controls how quickly the model updates its weights; it is not an evaluation metric.

• Wireshark captures packets and allows you to examine their contents, potentially revealing usernames and passwords sent without encryption.
• Netcat creates network connections and can send or receive data, but it is not primarily a packet-analysis tool.
• Nessus scans for known vulnerabilities and configuration issues; it generally would not prove that credentials are visible in transit.
• Nmap performs network discovery and port/service scanning, not detailed packet-content inspection.

• Identified risks
• Risk owners or responsible parties
• Likelihood and impact
• Risk response plans
• Current status
• Risk thresholds or trigger conditions

• Risk tolerance: The amount and type of risk an organization is willing to accept; it is not primarily a tracking document.
• Risk transfer: Moving the financial or operational impact of a risk to another party, such as through insurance or outsourcing.
• Risk analysis: The process of evaluating a risk’s likelihood and impact.

• Customer: Dual
• Date: Dual
• Sales: DirectQuery
• SalesAggregate: Import

• Sales – DirectQuery: Near-real-time data should not rely on an imported cache. DirectQuery sends queries to the source when visuals are loaded, allowing recent sales data to appear.
• SalesAggregate – Import: A weekly refresh is sufficient, and imported data generally gives faster visual performance because it is stored in Power BI’s in-memory cache.
• Customer and Date – Dual: These are dimension tables used with both the DirectQuery Sales table and the imported SalesAggregate table. Dual allows Power BI to use cached data when possible, while still behaving appropriately in queries involving DirectQuery data. This can improve performance and reduce unnecessary limited relationships.

• SAML: Enables federated authentication and single sign-on between the IdP and SaaS providers.
• OAuth tokens: Allow delegated application access; OAuth is not primarily the first step for employee SSO.
• Password vaulting: Stores or autofills multiple passwords but does not eliminate the separate credentials or provide true federation.

• GPU: A failure may cause no video output, but the PC usually still powers on.
• RAM: Can prevent booting or produce error beeps, but fans and power indicators generally work.
• CPU: Can prevent startup or booting, but it usually does not cause a completely lifeless system.

sql 
CREATE PROCEDURE dbo.usp_CreateOrder 
AS 
BEGIN 
    SET NOCOUNT ON; 
    SET XACT_ABORT ON; 


    BEGIN TRY 
        BEGIN TRANSACTION; 


        INSERT INTO dbo.Orders (/ columns /) 
        VALUES (/ values /); 


        SET @OrderID = SCOPE_IDENTITY(); 


        COMMIT TRANSACTION; 
    END TRY 
    BEGIN CATCH 
        IF @@TRANCOUNT > 0 
            ROLLBACK TRANSACTION; 


        THROW; 
    END CATCH; 
END;

• BEGIN TRY contains the transactional work.
• SCOPE_IDENTITY() retrieves the identity generated by the INSERT; it belongs after the insert, not as the error-handling logic.
• COMMIT runs only if all statements succeed.
• BEGIN CATCH handles failures.
• IF @@TRANCOUNT > 0 prevents attempting a rollback when no transaction is active.
• ROLLBACK undoes partial changes.
• THROW re-raises the original error with consistent details for the application.
• SET XACT_ABORT ON ensures many run-time errors automatically terminate and roll back the transaction.

1. Clear principles and boundaries — Employees have freedom, but decisions must remain within clear organizational values, policies and limits.
2. High degree of freedom — Managers are trusted to make decisions rather than seeking continual approval from senior management.
3. Frontline customer responsibility — Customer-facing managers should be empowered to manage customer relationships and respond quickly to needs.
4. Transparent and ethical information — Information should be openly available and used honestly, supporting trust and informed decision-making.

• Approve major information security policies
• Allocate funding and resources
• Set the organization’s risk appetite
• Ensure security supports business objectives

• Evaluating vendors is generally handled by security, procurement, or technical teams.
• Assessing risks is typically performed by security and risk-management professionals, with management accepting or prioritizing the risks.
• Monitoring regulatory adherence is usually handled by compliance, audit, or security functions.

• Blue team: Defends systems, monitors activity, and responds to attacks.
• Purple team: Coordinates red- and blue-team activities to improve defenses.
• White team: Oversees or manages the exercise, including rules and scope.

• Remote and global work: Access is based on the approved device, not a specific office or geographic location.
• Seamless login: Users may not need to repeatedly enter credentials on a recognized device.
• Limited equipment: It uses devices employees already have rather than requiring separate hardware.

• Geotagging: Restricts access based on location and may prevent legitimate remote work.
• Smart cards: Require issuing and managing additional physical equipment.
• Time-based logins: Limit access by time and do not provide a seamless authentication experience.

• A: Person Accounts cannot be merged directly with standard Contact records.
• C: There is no Account Setup option that automatically merges Person Account duplicates.
• D: Matching rules and duplicate rules can help identify or prevent duplicates, but they do not automatically merge Person Accounts. Also, relationship considerations do not change the basic merge capability.

• Microservices: An application-design approach that divides an application into smaller services. It does not inherently reduce the number of operating systems.
• Virtualization: Creates virtual machines, but each VM generally requires its own complete operating system. This improves isolation but does not minimize OS instances as effectively.
• Infrastructure as code: Uses code to automate infrastructure deployment and configuration. It improves consistency but does not determine how many operating systems are used.

• VM CPU, memory, disk, and network usage
• Storage transactions and latency
• App Service response time
• Database DTU or CPU utilization

• Azure Traffic Analytics analyzes network traffic flows and security patterns; it is not the general infrastructure metrics tool.
• Azure Activity Log records subscription-level control-plane operations, such as resource creation, deletion, or configuration changes.
• Azure Advisor provides recommendations about cost, security, reliability, performance, and operational excellence, but it is not the primary tool for investigating live metrics.

• Restrict a port to a defined number of MAC addresses
• Use statically assigned or “sticky” MAC addresses
• Shut down or restrict the port when violations occur

• Load balancer: Distributes application traffic; it does not protect switch MAC tables.
• IPS: May detect suspicious network activity, but is not the primary control for limiting switch MAC entries.
• NGFW: Filters traffic at the network boundary; it does not directly prevent MAC table flooding on access switches.

• Each Azure VM must have at least one network interface (NIC).
• A single NIC can have:

• Therefore, each of the five VMs needs only one NIC:

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

• ARP poisoning: Redirects or intercepts local network traffic; it would more likely affect communication paths or cause man-in-the-middle behavior.
• Jamming: Interferes with wireless signals. The scenario does not indicate a wireless outage.
• Kerberoasting: Attempts to obtain service-account password hashes from Kerberos; it is a credential attack, not typically a direct service outage.

• Keep earlier prompt versions.
• Identify the last version that produced acceptable output.
• Restore it as a baseline.
• Make small, controlled changes—ideally one significant change at a time.
• Test the output after each change.

• A: Discards useful information about what worked.
• B: Large simultaneous changes make it difficult to identify the cause of problems.
• D: Accepts output that does not meet the requirements.

• Server provisioning
• Operating systems and runtime infrastructure
• Scaling
• Much of the maintenance and patching

• Thin clients reduce endpoint hardware requirements but do not specifically streamline code deployment.
• Private cloud provides dedicated cloud infrastructure but usually requires more management and expense.
• Virtual machines improve resource utilization, but administrators still manage the VMs, operating systems, and deployments.

• B — Single customer login across properties: Customer 360 Identity provides centralized identity services, allowing an organization to recognize a customer across multiple digital properties and applications. This helps UC understand authenticated activity as part of a broader customer identity.

• C — Multi-brand support: Customer 360 Identity can support multiple brands and user experiences. Identity services can remain centralized while correlating a customer’s activity across different corporate brands or channels.

• A: Customer 360 Identity does not automatically populate all data into Customer 360 Data Manager and Customer 360 Audiences. Integration and data configuration are still required.
• D: Tracking anonymous activity and linking it after sign-up may be possible through broader customer-data and tracking implementations, but it is not the primary Customer 360 Identity benefit tested here. Identity focuses mainly on authentication, registration, and cross-property identity correlation.

• AWS AppSync is designed for serverless applications that need to retrieve and combine data from multiple sources.
• A pipeline resolver can invoke multiple functions or data-source resolvers, including resolvers connected to different DynamoDB tables.
• The application can receive the combined result through one GraphQL request, without requiring custom aggregation logic in the application.
• This is operationally efficient because AppSync manages the API layer and resolver execution.

• Athena Federated Query is intended primarily for analytics and ad hoc querying, not low-latency application data retrieval.
• Querying DynamoDB through Athena can consume DynamoDB read capacity and may affect table performance.
• It also introduces analytical-query overhead and is not the normal choice for a microservice web application.

Correct choices

• DB1: Azure Data Box Heavy
• Virtual machines: Azure Migrate

Why

• Replication with minimal downtime
• A test migration
• Final cutover after validation

• C series: CPU-optimized instances; not designed primarily for LLM training.
• G series: GPU instances generally optimized for graphics and some machine learning workloads, but not specifically large-scale model training efficiency.
• P series: Powerful GPU instances for ML training, but typically consume more energy than Trainium-based instances for suitable training workloads.

• The servers are powered on.
• The network is functioning.
• Devices can still reach the server network.

• ARP poisoning: Redirects or intercepts local network traffic; it usually affects communication paths rather than overwhelming a service.
• Jamming: Disrupts wireless or radio signals. It would not fit a system that remains accessible from devices on the server network.
• Kerberoasting: Attempts to crack service-account credentials from Kerberos tickets; it does not normally cause an immediate outage.

1. Find the subnet-mask increment in the octet where the prefix ends.
2. Identify the network address by finding the subnet boundary at or below the given IP.
3. The first usable address is network address + 1.
4. The broadcast address is one address before the next subnet.
5. The last usable address is broadcast - 1.

• 172.28.228.144/18

• 172.28.228.144/23

• The application failing to start or becoming unhealthy
• An incorrect probe path, port, or protocol
• The application needing more startup time
• Dependency or configuration failures
• A liveness probe being too aggressive

bash 
kubectl describe pod <pod-name> 
kubectl logs <pod-name> --previous

• Scale to more replicas: may hide the issue but does not diagnose it.
• Decrease initialDelaySeconds: makes probes run earlier and could worsen startup failures.
• Drain and reboot the node: node metrics are normal, so rebooting is not justified as the first step.

• Sensitive document shared during a Teams chat: Teams chat
• Sensitive document stored/shared in a Teams channel: Teams channel messages

• Files shared in a chat are generally stored in the sender’s OneDrive, but the relevant DLP context is the Teams chat message and its attachment.
• Files shared in a channel are stored in the team’s SharePoint site, but the relevant context is the Teams channel message.
• The DLP rule can then use an action such as restrict access to the content to prevent guest users from opening the sensitive document.

• 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.

• B: Developer Edition has limited user, storage, and data-volume capacity, making realistic community testing difficult.
• C: A Developer Edition org cannot contain sandboxes, so it cannot provide separate environments for development, integration, and UAT.
• E: A standalone Developer Edition org is not part of the production org’s deployment path, so change sets cannot be used to deploy from it directly to that production org. The team would need Metadata API, Salesforce CLI, or another deployment method.

• A: Allow SAN certificates — SANs are used to identify valid hostnames in a certificate. They do not bypass trust validation.
• C: Open the secure LDAP port — A blocked port would normally cause a timeout or connection-refused error, not certificate errors.
• D: Increase the TLS version on the RA — The issue concerns certificate trust, not the organization’s registration authority.

• Authentication: Verifies a user’s identity, such as username and password.
• Authorization: Determines what the authenticated user is allowed to access.
• Accounting: Records connection and usage details, such as login time or session duration.

• CIA: Confidentiality, integrity, and availability are broad security objectives, not a specific RADIUS function.
• ACL: An access control list contains permit/deny rules on systems or network devices. RADIUS can support access decisions but is not itself an ACL.
• PEM: Privacy-Enhanced Mail is also associated with certificate and key encoding formats; it is unrelated to RADIUS’s primary purpose.

• Error correction (ECC): Improves data reliability but does not maximize bandwidth.
• RAM voltage: Increasing voltage may affect stability or speed, but it is not the primary method for increasing module bandwidth.
• Physical module size: Refers to the capacity or form factor of the RAM, not its data-transfer bandwidth.

• Password spraying: Tries a few common passwords against many accounts; no indication of repeated login attempts.
• Remote-access Trojan (RAT): Could install malware, but it does not explain how the attacker obtained the administrator’s credentials.
• Dictionary attack: Tries words or common passwords against an account; again, the scenario specifically highlights Telnet’s lack of encryption.

• Generates a syslog message
• Shuts down the PoE port
• Places the port into error-disabled (err-disabled) state
• Frees the power allocation

• A device starting to draw power does not necessarily generate a syslog message.
• Monitoring does not pause data traffic while checking power.
• Drawing less than the configured minimum does not automatically mean the device has failed and should be disconnected.

• Monitoring: Detects activity but does not remove the underlying risk.
• Patching: Useful for systems that must remain operational, but these desktops are unused.
• Isolating: Can be a temporary containment measure, but permanently removing unnecessary systems is more appropriate.

• The VM keeps its configuration, disks, IP settings, and associated resources.
• The operation may cause downtime.
• You cannot guarantee that it will move specifically to Host2; Azure selects the new host.
• Update management is for update configuration, not host relocation.
• Moving to another subscription does not move the VM to a different physical host.
• Usage location is unrelated to VM placement.

• Continuous deployment: Automates software releases; it does not specifically test input handling.
• Static code analysis: Examines source or compiled code without executing it. It can find coding flaws but does not directly stress the application with malformed inputs.
• Manual peer review: Developers inspect code or design manually. Useful, but not the best practice specifically for testing how a live product handles invalid input.

• Customize Opportunity Contact Role

• Add the Opportunity Contact Role related list to the Opportunity page layout

• Campaign Member Role relates contacts or leads to campaigns, not opportunities.
• Campaign Member related list would expose campaign participation, not the stakeholders for the opportunity.
• Customize Campaign Role also concerns campaigns.

• CSIRT: A Computer Security Incident Response Team that handles and coordinates incident response.
• CVSS: A scoring system used to rate the severity of vulnerabilities.
• SOAR: Security Orchestration, Automation, and Response technology used to automate security workflows.

• 16GB RAM: A 64-bit OS is needed to use more than roughly 4GB effectively, but RAM capacity does not prove the CPU supports 64-bit operation.
• 500GB HDD: Storage capacity has no bearing on OS architecture.
• 1Gbps Ethernet: Network speed is unrelated to CPU architecture.

• tag=Priv searches the tag field for values beginning with Priv. The wildcard can match the remaining characters, so it matches Privileged.
• tag=Priv would search for the exact tag Priv, not Privileged.
• tag=priv* uses lowercase priv; tag matching is treated as case-sensitive here, so it may not match the tag Privileged.
• tag=privileged uses the wrong capitalization for the exact tag.