---
name: cloud-migration-planning
description: >
  Plan and execute cloud migrations with assessment, database migration,
  application refactoring, and cutover strategies across AWS, Azure, and GCP.
---

# Cloud Migration Planning

## Table of Contents

- [Overview](#overview)
- [When to Use](#when-to-use)
- [Quick Start](#quick-start)
- [Reference Guides](#reference-guides)
- [Best Practices](#best-practices)

## Overview

Cloud migration planning involves assessing current infrastructure, designing migration strategies, executing migrations with minimal downtime, and validating outcomes. Support lift-and-shift, replatforming, and refactoring approaches for smooth cloud adoption.

## When to Use

- Moving from on-premises to cloud
- Cloud platform consolidation
- Legacy system modernization
- Reducing data center costs
- Improving scalability and availability
- Meeting compliance requirements
- Disaster recovery enhancement
- Technology refresh initiatives

## Quick Start

Minimal working example:

```python
# Cloud migration assessment tool
from enum import Enum
from typing import Dict, List, Tuple
from dataclasses import dataclass

class MigrationStrategy(Enum):
    LIFT_AND_SHIFT = "lift_and_shift"  # Rehost
    REPLATFORM = "replatform"          # Rehost with optimizations
    REFACTOR = "refactor"              # Rebuild for cloud
    REPURCHASE = "repurchase"          # Switch to SaaS
    RETIRE = "retire"                  # Decommission

class ApplicationComplexity(Enum):
    LOW = 1
    MEDIUM = 2
    HIGH = 3

@dataclass
class ApplicationAssessment:
    name: str
    complexity: ApplicationComplexity
    dependencies: List[str]
    estimated_effort: int  # days
    business_criticality: int  # 1-10
    current_costs: float  # annual
// ... (see reference guides for full implementation)
```

## Reference Guides

Detailed implementations in the `references/` directory:

| Guide | Contents |
|---|---|
| [Migration Assessment and Planning](references/migration-assessment-and-planning.md) | Migration Assessment and Planning |
| [Database Migration Strategies](references/database-migration-strategies.md) | Database Migration Strategies |
| [Terraform Migration Infrastructure](references/terraform-migration-infrastructure.md) | Terraform Migration Infrastructure |
| [Cutover Validation Checklist](references/cutover-validation-checklist.md) | Cutover Validation Checklist |

## Best Practices

### ✅ DO

- Perform thorough discovery and assessment
- Run parallel systems during transition
- Test thoroughly before cutover
- Have rollback plan ready
- Monitor closely post-migration
- Document all changes
- Train operations team
- Maintain previous systems temporarily

### ❌ DON'T

- Rush migration without planning
- Migrate without testing
- Forget rollback procedures
- Ignore dependencies
- Skip stakeholder communication
- Migrate everything at once
- Forget to update documentation