Multi Cloud Architecture

--- name: multi-cloud-architecture description: Design multi-cloud architectures using a decision framework to select and integrate services across AWS, Azure, GCP, and OCI. Use when building multi-cloud systems, avoiding vendor lock-in, or leveraging best-of-breed services from multiple providers. --- # Multi-Cloud Architecture Decision framework and patterns for architecting applications across AWS, Azure, GCP, and OCI. ## Purpose Design cloud-agnostic architectures and make informed decisions about service selection across cloud providers. ## When to Use - Design multi-cloud strategies - Migrate between cloud providers - Select cloud services for specific workloads - Implement cloud-agnostic architectures - Optimize costs across providers ## Cloud Service Comparison ### Compute Services | AWS | Azure | GCP | OCI | Use Case | | ------- | ------------------- | --------------- | ------------------- | ------------------ | | EC2 | Virtual Machines | Compute Engine | Compute | IaaS VMs | | ECS | Container Instances | Cloud Run | Container Instances | Containers | | EKS | AKS | GKE | OKE | Kubernetes | | Lambda | Functions | Cloud Functions | Functions | Serverless | | Fargate | Container Apps | Cloud Run | Container Instances | Managed containers | ### Storage Services | AWS | Azure | GCP | OCI | Use Case | | ------- | --------------- | --------------- | -------------- | -------------- | | S3 | Blob Storage | Cloud Storage | Object Storage | Object storage | | EBS | Managed Disks | Persistent Disk | Block Volumes | Block storage | | EFS | Azure Files | Filestore | File Storage | File storage | | Glacier | Archive Storage | Archive Storage | Archive Storage | Cold storage | ### Database Services | AWS | Azure | GCP | OCI | Use Case | | ----------- | ---------------- | ------------- | ------------------- | --------------- | | RDS | SQL Database | Cloud SQL | MySQL HeatWave | Managed SQL | | DynamoDB | Cosmos DB | Firestore | NoSQL Database | NoSQL | | Aurora | PostgreSQL/MySQL | Cloud Spanner | Autonomous Database | Distributed SQL | | ElastiCache | Cache for Redis | Memorystore | OCI Cache | Caching | Reference: See references/service-comparison.md for complete comparison ## Multi-Cloud Patterns ### Pattern 1: Single Provider with DR - Primary workload in one cloud - Disaster recovery in another - Database replication across clouds - Automated failover ### Pattern 2: Best-of-Breed - Use best service from each provider - AI/ML on GCP - Enterprise apps on Azure - Regulated data platforms on OCI - General compute on AWS ### Pattern 3: Geographic Distribution - Serve users from nearest cloud region - Data sovereignty compliance - Global load balancing - Regional failover ### Pattern 4: Cloud-Agnostic Abstraction - Kubernetes for compute - PostgreSQL for database - S3-compatible storage (MinIO) - Open source tools ## Cloud-Agnostic Architecture ### Use Cloud-Native Alternatives - Compute: Kubernetes (EKS/AKS/GKE/OKE) - Database: PostgreSQL/MySQL (RDS/SQL Database/Cloud SQL/MySQL HeatWave) - Message Queue: Apache Kafka or managed streaming (MSK/Event Hubs/Confluent/OCI Streaming) - Cache: Redis (ElastiCache/Azure Cache/Memorystore/OCI Cache) - Object Storage: S3-compatible API - Monitoring: Prometheus/Grafana - Service Mesh: Istio/Linkerd ### Abstraction Layers `` Application Layer ↓ Infrastructure Abstraction (Terraform) ↓ Cloud Provider APIs ↓ AWS / Azure / GCP / OCI ` ## Cost Comparison ### Compute Pricing Factors - **AWS:** On-demand, Reserved, Spot, Savings Plans - **Azure:** Pay-as-you-go, Reserved, Spot - **GCP:** On-demand, Committed use, Preemptible - **OCI:** Pay-as-you-go, annual commitments, burstable/flexible shapes, preemptible instances ### Cost Optimization Strategies 1. Use reserved/committed capacity (30-70% savings) 2. Leverage spot/preemptible instances 3. Right-size resources 4. Use serverless for variable workloads 5. Optimize data transfer costs 6. Implement lifecycle policies 7. Use cost allocation tags 8. Monitor with cloud cost tools **Reference:** See references/multi-cloud-patterns.md` ## Migration Strategy ### Phase 1: Assessment - Inventory current infrastructure - Identify dependencies - Assess cloud compatibility - Estimate costs ### Phase 2: Pilot - Select pilot workload - Implement in target cloud - Test thoroughly - Document learnings ### Phase 3: Migration - Migrate workloads incrementally - Maintain dual-run period - Monitor performance - Validate functionality ### Phase 4: Optimizatio