GCP & Azure Fundamentals for Multi-Cloud

Multi-Cloud Comparison & Decision Framework

4 min read

Solutions Architects must navigate multi-cloud discussions with confidence. This lesson provides comparison frameworks for interview scenarios.

Service Equivalency Matrix

Compute Services

Category AWS GCP Azure
VMs EC2 Compute Engine Virtual Machines
Serverless Compute Lambda Cloud Functions Azure Functions
Container Serverless Fargate Cloud Run Container Apps
Kubernetes EKS GKE AKS
Batch Processing AWS Batch Batch Azure Batch

Storage Services

Category AWS GCP Azure
Object Storage S3 Cloud Storage Blob Storage
Block Storage EBS Persistent Disk Managed Disks
File Storage EFS Filestore Azure Files
Archive S3 Glacier Archive Storage Archive Storage
Cold Tier S3-IA Nearline/Coldline Cool/Cold

Database Services

Category AWS GCP Azure
Relational (Managed) RDS Cloud SQL Azure SQL
Relational (Cloud-Native) Aurora AlloyDB/Spanner Azure SQL Hyperscale
NoSQL Key-Value DynamoDB Firestore/Bigtable Cosmos DB
Data Warehouse Redshift BigQuery Synapse Analytics
Cache ElastiCache Memorystore Azure Cache
Graph Neptune - Cosmos DB (Gremlin)

Networking Services

Category AWS GCP Azure
Virtual Network VPC VPC VNet
Load Balancer (L4) NLB Network LB Azure LB
Load Balancer (L7) ALB HTTP(S) LB App Gateway
CDN CloudFront Cloud CDN Azure CDN/Front Door
DNS Route 53 Cloud DNS Azure DNS
VPN Site-to-Site VPN Cloud VPN VPN Gateway
Direct Connect Direct Connect Dedicated Interconnect ExpressRoute

Interview Question: Multi-Cloud Selection

Q: "A financial services company is evaluating AWS, GCP, and Azure. How would you approach the decision?"

A: Use a structured evaluation framework:

1. Existing Technology Stack

Factor AWS Wins GCP Wins Azure Wins
Microsoft Ecosystem - - Office 365, AD, Teams
Google Workspace - Gmail, Drive integration -
VMware Workloads VMware Cloud on AWS Google VMware Engine Azure VMware Solution
Oracle Workloads RDS Oracle Bare Metal Azure Oracle partnership

2. Workload Requirements

Data Analytics Heavy:

  • GCP: BigQuery (serverless, ML integration)
  • AWS: Redshift (mature, broad ecosystem)
  • Azure: Synapse (Power BI integration)

Enterprise Applications:

  • Azure: SAP, Microsoft apps, AD
  • AWS: Broadest SAP support
  • GCP: Growing SAP support

Machine Learning:

  • GCP: Vertex AI, TPUs, BigQuery ML
  • AWS: SageMaker (comprehensive)
  • Azure: Azure ML, OpenAI integration

3. Global Network & Latency

Provider Network Strength
GCP Premium tier (Google backbone), global LB
AWS Largest footprint (32+ regions)
Azure 60+ regions, strong in government

4. Cost Considerations

Cost Leaders by Category:

  • Compute (sustained): GCP (automatic sustained discounts)
  • Egress: GCP (generally lower than AWS)
  • Storage: Azure (competitive in enterprise tiers)
  • Spot/Preemptible: Similar across all (80-90% discount)

Multi-Cloud Architecture Patterns

Pattern 1: Best-of-Breed

Use each cloud for its strengths:

AWS: Core infrastructure, web applications
GCP: BigQuery for analytics, ML training
Azure: Office 365 integration, identity

Pros: Optimal for each workload Cons: Operational complexity, data movement costs

Pattern 2: Active-Passive DR

Primary on one cloud, DR on another:

Primary: AWS (us-east-1, us-west-2)
DR: Azure (East US 2)

Pros: Vendor independence, true DR Cons: Skill duplication, sync complexity

Pattern 3: Geo-Distribution

Different clouds for different regions:

Americas: AWS
Europe: Azure (GDPR compliance)
Asia: GCP (network performance)

Pros: Regulatory compliance, local performance Cons: Management overhead

Interview Question: Multi-Cloud Trade-offs

Q: "What are the main challenges of multi-cloud architectures?"

A:

Challenge Impact Mitigation
Skill Requirements Need expertise in 2-3 platforms Invest in training, use abstraction layers
Data Egress Costs Significant for large data movement Minimize cross-cloud traffic, replicate strategically
Management Complexity Different APIs, tools, consoles Use Terraform, Kubernetes for abstraction
Security Consistency Different IAM models, policies Standardize with identity federation
Vendor Support Blame game between providers Clear service boundaries, SLAs

Cloud Selection Decision Tree

Starting Point: What's your primary workload?

Enterprise/Microsoft-centric?
  └── Azure (AD, Office 365, Dynamics)

Data/Analytics-heavy?
  └── GCP (BigQuery, Vertex AI)

Web-scale/Microservices?
  └── AWS (broadest services, largest community)

Hybrid/On-premises integration?
  └── Azure (Arc, Stack) or AWS (Outposts)

Multi-region with premium networking?
  └── GCP (global VPC, global LB)

Cost-sensitive compute?
  └── GCP (sustained use discounts) or AWS (Savings Plans)

Abstraction Strategies

Infrastructure as Code

  • Terraform: Multi-cloud IaC standard
  • Pulumi: Programming language-based IaC
  • Crossplane: Kubernetes-native cloud management

Container Orchestration

  • Kubernetes: Portable across all clouds
  • Anthos (GCP): Multi-cloud Kubernetes management
  • Azure Arc: Multi-cloud management from Azure

Serverless Abstraction

  • Knative: Portable serverless on Kubernetes
  • KEDA: Event-driven autoscaling
  • Dapr: Microservices runtime abstraction

Interview Tip: When discussing multi-cloud, always address the trade-offs between flexibility and complexity. The best answer depends on the organization's specific needs, not a one-size-fits-all recommendation.

This concludes the GCP & Azure Fundamentals module. Test your knowledge with the module quiz. :::

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Module 3: GCP & Azure Fundamentals for Multi-Cloud

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