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Introduction

Migrating enterprise applications to AWS is not simply copying servers or databases.

A successful migration requires careful planning across:

• Infrastructure
• Networking
• Security
• Applications
• Databases
• Storage
• Monitoring
• Disaster Recovery
• CI/CD
• Compliance
• Cost Optimization

Skipping even one critical step can lead to:

• Downtime
• Data loss
• Security vulnerabilities
• Poor performance
• Failed deployments
• Customer impact

This guide provides a complete enterprise migration checklist that architects, technical leads, and DevOps engineers can use before, during, and after migrating Spring Boot applications to AWS.

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Enterprise Migration Lifecycle

flowchart LR

ASSESS[Assessment]

ASSESS --> PLAN[Planning]

PLAN --> DESIGN[Architecture Design]

DESIGN --> BUILD[Build AWS Environment]

BUILD --> MIGRATE[Migration]

MIGRATE --> VALIDATE[Validation]

VALIDATE --> CUTOVER[Production Cutover]

CUTOVER --> OPTIMIZE[Optimization]

OPTIMIZE --> MODERNIZE[Continuous Modernization]

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Phase 1 — Business Assessment

Before migrating, understand why the migration is being performed.

Business Goals

✔ Reduce infrastructure cost

✔ Improve scalability

✔ Increase availability

✔ Improve disaster recovery

✔ Faster deployments

✔ Cloud modernization

✔ Regulatory compliance

✔ Global expansion

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Application Inventory

Create a complete inventory.

Document:

• Application Name
• Owner
• Business Criticality
• Technology Stack
• Spring Boot Version
• Java Version
• Database
• Dependencies
• Third-party Integrations
• Batch Jobs
• APIs

Example:

Application	Critical	Technology
Payment API	High	Spring Boot
Claims Portal	High	Angular + Spring Boot
Notification Service	Medium	Spring Boot

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Phase 2 — Application Assessment

Understand how the application works.

Architecture Review

Document:

• Monolith or Microservices
• REST APIs
• Scheduled Jobs
• Batch Processing
• Kafka/SQS/SNS
• File Processing
• Authentication
• External APIs

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Dependency Mapping

Identify:

• Databases
• Shared Libraries
• External Services
• Authentication Systems
• DNS
• LDAP
• Active Directory
• Message Brokers
• FTP Servers

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Migration Strategy (7 Rs)

Choose one strategy.

Strategy	Description
Rehost	Lift & Shift
Replatform	Small optimizations
Refactor	Cloud Native
Repurchase	SaaS Replacement
Retire	Remove application
Retain	Keep On-Prem
Relocate	Move VMware workloads

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Phase 3 — AWS Landing Zone

Create a secure AWS foundation.

Checklist:

✔ AWS Organization

✔ Multi-Account Strategy

✔ IAM Identity Center

✔ CloudTrail

✔ AWS Config

✔ GuardDuty

✔ Security Hub

✔ AWS Backup

✔ KMS

✔ Logging Account

✔ Monitoring Account

✔ SCP Policies

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Phase 4 — Networking Checklist

Create networking before application deployment.

VPC

✔ CIDR Planning

✔ Public Subnets

✔ Private Subnets

✔ NAT Gateway

✔ Internet Gateway

✔ Route Tables

✔ Network ACLs

✔ Security Groups

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Hybrid Connectivity

If On-Prem exists:

✔ Site-to-Site VPN

✔ Direct Connect

✔ Transit Gateway

✔ DNS Resolution

✔ Firewall Rules

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Network Architecture

flowchart TD
    INET["Internet"]
    CF["CloudFront"]
    WAF["AWS WAF"]
    ALB["Application Load Balancer"]
    PRIV["Private Subnet"]
    SB["Spring Boot Services"]
    DB["Amazon Aurora"]

    INET --> CF --> WAF --> ALB --> PRIV --> SB --> DB

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Phase 5 — Security Checklist

Security must be implemented before production deployment.

IAM

✔ Least Privilege

✔ IAM Roles

✔ IAM Policies

✔ MFA

✔ Temporary Credentials

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Secrets

Never store credentials in code.

Use:

• AWS Secrets Manager
• Systems Manager Parameter Store

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Encryption

Enable encryption for:

✔ EBS

✔ S3

✔ Aurora

✔ DynamoDB

✔ RDS

✔ Backups

✔ Secrets

Use AWS KMS for centralized key management.

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Web Security

✔ AWS WAF

✔ Shield

✔ TLS

✔ HTTPS

✔ ACM Certificates

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Phase 6 — Database Migration

Review every database.

Checklist:

✔ Backup

✔ Schema Review

✔ Data Validation

✔ AWS SCT

✔ AWS DMS

✔ CDC

✔ Performance Testing

✔ Index Review

✔ Stored Procedure Review

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Database Migration Workflow

flowchart LR
    SRC["Source Database"]
    SCT["AWS SCT"]
    DMS["AWS DMS"]
    AURORA["Amazon Aurora"]
    VALID["Validation"]
    PROD["Production"]

    SRC --> SCT --> DMS --> AURORA --> VALID --> PROD

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Phase 7 — Storage Migration

Review:

✔ Amazon S3

✔ DataSync

✔ Snowball

✔ EFS

✔ FSx

✔ Lifecycle Policies

✔ Versioning

✔ Cross-Region Replication

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Phase 8 — Spring Boot Readiness

Review application configuration.

Checklist:

✔ Java Version

✔ Spring Boot Version

✔ Environment Variables

✔ External Configuration

✔ Logging

✔ Health Checks

✔ Graceful Shutdown

✔ Container Readiness

✔ Database Connection Pool

✔ Retry Logic

✔ Circuit Breaker

✔ Distributed Tracing

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Phase 9 — Containerization

If deploying containers:

✔ Dockerfile

✔ Multi-stage Build

✔ Health Check

✔ Image Scanning

✔ Amazon ECR

✔ ECS or EKS Deployment

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Container Workflow

flowchart LR
    SB["Spring Boot"]
    DOCKER["Docker"]
    ECR["Amazon ECR"]
    ECS["Amazon ECS"]
    ALB["Application Load Balancer"]

    SB --> DOCKER --> ECR --> ECS --> ALB

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Phase 10 — CI/CD

Deployment pipeline should include:

✔ Source Control

✔ Build

✔ Unit Tests

✔ Security Scan

✔ Code Quality

✔ Container Build

✔ Deployment

✔ Smoke Test

✔ Rollback

Typical services:

• GitHub
• AWS CodePipeline
• AWS CodeBuild
• CodeDeploy
• Jenkins
• GitLab CI

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Phase 11 — Monitoring

Enable monitoring before go-live.

Checklist:

✔ CloudWatch

✔ CloudTrail

✔ AWS X-Ray

✔ OpenTelemetry

✔ Prometheus

✔ Grafana

✔ Dashboards

✔ Alerts

✔ Log Retention

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Monitoring Architecture

flowchart LR
    SB["Spring Boot"]
    CW["CloudWatch"]
    ALARM["Alarms"]
    SNS["Amazon SNS"]
    OPS["Operations Team"]

    SB --> CW --> ALARM --> SNS --> OPS

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Phase 12 — Performance Testing

Before production:

✔ Load Testing

✔ Stress Testing

✔ Spike Testing

✔ Failover Testing

✔ Database Benchmarking

✔ API Response Time

✔ Cache Validation

✔ Autoscaling Validation

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Phase 13 — Disaster Recovery

Review:

✔ RTO

✔ RPO

✔ Backup Frequency

✔ Cross-Region Replication

✔ Multi-AZ

✔ Restore Testing

✔ Failover Validation

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Phase 14 — Production Cutover

Before switching traffic:

✔ Database Sync Complete

✔ CDC Delay Near Zero

✔ Smoke Tests Passed

✔ Monitoring Enabled

✔ Rollback Plan Ready

✔ Support Team Available

✔ Stakeholders Notified

✔ DNS Ready

✔ Maintenance Window Approved

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Cutover Workflow

flowchart LR
    VAL["Validation"]
    PA["Production Approval"]
    DNS["DNS Switch"]
    VER["Application Verification"]
    SIGN["Business Sign-off"]

    VAL --> PA --> DNS --> VER --> SIGN

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Phase 15 — Post Migration

Immediately after deployment:

✔ Monitor CPU

✔ Memory

✔ Database Connections

✔ Error Rate

✔ API Latency

✔ User Login

✔ Background Jobs

✔ Batch Jobs

✔ Cost Monitoring

✔ Security Monitoring

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Phase 16 — Cost Optimization

Review:

✔ EC2 Right Sizing

✔ Auto Scaling

✔ Savings Plans

✔ Reserved Instances

✔ S3 Lifecycle

✔ Storage Tiering

✔ Idle Resources

✔ Compute Optimizer

✔ Cost Explorer

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Enterprise Architecture

flowchart TD
    U["Users"]
    CF["CloudFront"]
    WAF["AWS WAF"]
    ALB["Application Load Balancer"]
    ECS["Amazon ECS"]
    RDS["Amazon Aurora"]
    SQS["Amazon SQS"]
    EB["Amazon EventBridge"]
    S3["Amazon S3"]
    CW["CloudWatch"]
    SNS["Amazon SNS"]

    U --> CF --> WAF --> ALB --> ECS --> RDS

    ECS --> SQS
    ECS --> EB
    ECS --> S3
    ECS --> CW

    CW --> SNS

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Migration Readiness Scorecard

Area	Status
Business Assessment	✅
Application Inventory	✅
Networking	✅
Security	✅
Database	✅
Storage	✅
CI/CD	✅
Monitoring	✅
Disaster Recovery	✅
Production Validation	✅

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Common Migration Mistakes

Mistake	Recommendation
Migrating without assessment	Perform detailed discovery first
Ignoring dependencies	Build dependency maps
No rollback strategy	Prepare tested rollback plans
Hardcoded secrets	Use Secrets Manager
No monitoring	Configure observability before production
Poor performance testing	Validate under expected workloads
Skipping DR testing	Test recovery regularly

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Best Practices

• Start with business objectives.
• Build a secure AWS Landing Zone first.
• Automate infrastructure with Infrastructure as Code.
• Validate every migration wave.
• Use Blue/Green or Canary deployments where appropriate.
• Keep rollback procedures documented.
• Monitor continuously after go-live.
• Optimize costs after stabilization.
• Modernize incrementally rather than rewriting everything.
• Review architecture regularly for continuous improvement.

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Interview Questions

1. What phases are involved in an enterprise cloud migration?
2. What should be verified before production cutover?
3. How do you reduce migration risk?
4. Why is dependency mapping important?
5. What is an AWS Landing Zone?
6. How do you validate a successful migration?
7. What monitoring should be enabled before production?
8. What should be included in a rollback plan?

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Summary

Enterprise cloud migration is a structured transformation program rather than a single technical activity.

A successful AWS migration requires careful planning across business, architecture, networking, security, databases, storage, deployment, monitoring, disaster recovery, and operational readiness.

For Spring Boot applications, following a comprehensive migration checklist helps ensure:

• Minimal downtime
• Secure deployments
• Reliable production cutovers
• Strong observability
• Optimized costs
• Improved scalability
• Faster software delivery
• Long-term cloud success

By treating migration as an incremental modernization journey instead of a one-time infrastructure move, organizations can fully realize the benefits of AWS while reducing operational risk.

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