Cloud migration is the process of moving applications, data, and IT infrastructure from on-premise data centres or legacy hosting to cloud platforms. Cloud migration enables organisations to reduce capital infrastructure costs, improve scalability, leverage cloud capabilities, and reduce operational burden. However, migrations are complex projects requiring careful planning, coordination, and risk management.
Migration Motivations
Organisations migrate to cloud for various reasons:
Cost reduction - Eliminating capital infrastructure investment and physical data centre operating costs.
Scalability - Accessing dynamic scaling without capital infrastructure expansion.
Reliability - Leveraging cloud providers' geographic redundancy and availability.
Modern capabilities - Accessing cloud-native features and managed services.
Business agility - Reducing time and cost for infrastructure changes.
Migration Strategies
Different migration strategies suit different situations:
Lift and shift - Migrating applications unchanged to cloud. Fastest but may not optimise for cloud. Suitable for stable applications without immediate change needs.
Replatform - Minor optimisations for cloud whilst maintaining core architecture. Moderate effort, moderate optimisation.
Refactor/Re-architect - Redesigning applications for cloud-native approaches. Maximum optimisation but highest effort and risk.
Repurchase - Replacing on-premise applications with cloud SaaS offerings. Can be fastest but requires application changes.
Retire - Decommissioning applications no longer needed. Often overlooked but can be most cost-effective.
Retain - Leaving some applications on-premise whilst migrating others. Gradual approach reducing risk.
Assessment and Planning
Successful migrations begin with thorough assessment:
Application inventory - Cataloguing all applications, their characteristics, dependencies, and business value.
Dependency mapping - Understanding application dependencies and data flows.
Cost analysis - Understanding current costs and projecting cloud costs.
Business case - Quantifying migration benefits and justifying investment.
Readiness assessment - Evaluating organisational readiness for cloud (skills, processes, culture).
Migration Phases
Migrations typically proceed in phases:
Pilot phase - Migrating small, non-critical applications to prove approach and build capability.
Wave migrations - Migrating applications in prioritised waves based on business value, complexity, and dependencies.
Final phase - Migrating remaining applications and decommissioning legacy infrastructure.
Phased approaches reduce risk, enable learning, and maintain business continuity.
Data Migration
Data migration is often the most challenging aspect:
Data assessment - Understanding data volumes, quality, dependencies, and compliance requirements.
Migration tools - Using migration tools (AWS Database Migration Service, others) for efficient transfer.
Validation - Thoroughly validating data completeness and accuracy post-migration.
Cutover coordination - Planning cutover to minimise business disruption.
Rollback planning - Preparing to revert if issues occur post-cutover.
Network and Connectivity
Connecting on-premise and cloud environments:
VPN connections - Virtual private networks enabling secure communication during migration.
Direct connections - Dedicated network connections (AWS Direct Connect) for higher bandwidth and reliability.
DNS management - Planning DNS transitions ensuring traffic routes appropriately.
Hybrid networking - Managing both on-premise and cloud resources simultaneously during migration.
Downtime Management
Minimising business disruption is critical:
Parallel running - Running old and new systems simultaneously, switching when validated.
Staged cutover - Cutting over gradually by segment or region.
Blue-green deployment - Deploying new infrastructure alongside existing, switching when ready.
Automated testing - Automated verification enabling rapid detection of issues.
Rollback capability - Maintaining ability to quickly revert if issues occur.
Compliance and Security
Migrations must maintain security and compliance:
Compliance requirements - Understanding regulatory requirements (HIPAA, GDPR, PCI-DSS) and ensuring cloud setup complies.
Data residency - Some regulations require data to remain in specific locations.
Encryption - Encrypting data in transit and at rest during migration.
Access controls - Ensuring appropriate access controls throughout migration.
Audit trails - Maintaining logs of all migration activities for compliance and troubleshooting.
Skills and Capability
Successful migrations require skills:
Cloud expertise - Teams experienced with target cloud platform.
Migration tools - Expertise with migration tools and techniques.
Application expertise - Understanding existing applications and their needs.
Project management - Managing complex, interdependent activities.
Change management - Helping organisations adapt to cloud approaches.
Training and hiring may be necessary to fill skill gaps.
Cost Management
Migration costs require management:
Hidden costs - Data transfer, licensing changes, and retraining add to direct infrastructure costs.
Right-sizing - Optimising cloud resource sizing post-migration reduces ongoing costs.
Reserved instances - Committing to baseline capacity in cloud reduces costs.
Decommissioning - Shutting down on-premise systems reduces costs.
Cloud migrations often cost more than initial projections; careful management is essential.
Cloud Migration at PixelForce
PixelForce has guided organisations through cloud migrations, typically to AWS. Our experience includes assessing applications, planning phased migrations, managing data migration, and refactoring applications for cloud-native approaches. Rather than simple lift-and-shift, we often recommend moderate refactoring optimising for cloud whilst balancing effort.
Common Migration Challenges
Migrations face predictable challenges:
Skills gaps - Existing teams lack cloud expertise, requiring training or hiring.
Legacy system constraints - Old systems difficult to migrate, may need replacement.
Data complexity - Complex data migrations create risk and require careful planning.
Integration complexity - Integrations between systems complicate migration.
Organizational resistance - Change resistance can undermine migrations.
Addressing these challenges through thorough planning, skills development, and change management is essential.
Post-Migration Optimisation
Migration is not the end:
Performance tuning - Optimising applications and infrastructure post-migration.
Cost optimisation - Right-sizing instances, eliminating waste, and negotiating costs.
Capability leverage - Leveraging cloud-native features and managed services.
Continuous improvement - Ongoing optimisation and refinement.
Conclusion
Cloud migration enables organisations to access cloud benefits whilst managing complexity through strategic planning, phased approaches, and careful execution. By assessing applications and infrastructure thoroughly, choosing appropriate migration strategies, managing risks, developing necessary skills, and continuously optimising post-migration, organisations successfully transition to cloud platforms.