Subtask 5.2: Reliability

**CASE STUDY: Dress4Win** **Company Overview:** Dress4Win is a web-based retail company that helps users organize their wardrobes. **Current Environment:** Colocated data center. Tomcat app servers, Nginx web servers, MySQL databases, Redis caching. 100TB of image data on SAN. **Business Requirements:** Migrate to cloud to handle seasonal spikes (Black Friday). Reduce CapEx. Enable rapid prototyping. **Executive Statements:** CEO: 'Innovate faster, stop worrying about servers.' CFO: 'Move to OpEx. Ensure PCI-DSS compliance.' CTO: 'Modernize stack but migrate quickly first.' **Technical Requirements:** Secure hybrid connectivity during migration. PCI-DSS compliance. Automated scaling. CI/CD for microservices. **Constraints:** Migration must be completed before Q4 holiday season (6 months). Limited budget for refactoring during initial migration. **QUESTION:** To handle the Black Friday seasonal spikes for the initially migrated Compute Engine workloads, which TWO actions should you take? (Select TWO)

**CASE STUDY: TerramEarth** **Company Overview:** TerramEarth manufactures heavy equipment. 2 million vehicles in the field. **Current Environment:** Vehicles send telemetry via cellular. Processing 100,000 msgs/sec. On-prem Hadoop cluster. **Business Requirements:** Predict equipment failure. Reduce warranty costs. Provide fleet dashboard. **Executive Statements:** CEO: 'Monetize data.' CFO: 'Storage costs spiraling.' CTO: 'Need scalable ingestion and ML.' **Technical Requirements:** Ingest 500,000 msgs/sec. Store petabytes cost-effectively. Train ML models. Real-time anomaly detection. **Constraints:** Intermittent connectivity. Strict vehicle authentication. **QUESTION:** To ensure the reliability of the new ingestion pipeline, the operations team wants to implement SRE practices. How should they measure the performance of the ingestion API?

CASE STUDY: MediSecure Overview: Telehealth provider, 1500 employees, $300M revenue. Core app on AWS, 3 acquired clinics on VMware, fragmented EHRs, Active Directory. Business Req: Unify patient records, integrate clinics in 90 days, launch patient portal. Execs: CEO wants rapid integration; CFO wants CapEx to OpEx; CISO demands strict HIPAA/GDPR compliance. Tech Req: End-to-end PHI encryption, comprehensive audit logging, hybrid connectivity to clinics, DR (RPO 5m, RTO 1h). Constraints: Clinics have low bandwidth, high staff turnover requires automated IAM, legacy EHRs cannot be modified immediately. QUESTION: To ensure the reliability of the new patient portal, the operations team wants to implement SRE practices. How should they define when it is safe to release new features?

Your SRE team is defining Service Level Indicators (SLIs) for a user-facing web application. Which metric is the most appropriate SLI to measure the user experience?

You are defining the monitoring strategy for a new e-commerce checkout service. You need to establish a Service Level Indicator (SLI) that accurately reflects the user's experience of the service's reliability. Which metric is the most appropriate SLI?

A global streaming service is planning for a major live event that is expected to generate 10x their normal traffic. They use Compute Engine, Cloud SQL, and Cloud Load Balancing. To ensure capacity and reliability during the event, which THREE actions should they take in advance? (Select THREE)