Lessons Learned Migrating Massive Global Mapping Esri Apps to AWS

Why Large Esri Migrations Succeed or Fail

Most Esri modernizations look simple on a whiteboard. Move ArcGIS Enterprise out of the datacenter, stand it up on AWS, rebuild the services, and containerize where it makes sense. In reality, large-scale Esri migrations are complex, operationally intensive projects. Global mapping footprints often involve thousands of services, dozens of integrations, and years of accumulated workflows. Success depends on disciplined sequencing, accurate baselining, and building the AWS foundation before touching ArcGIS.

The migrations I have led all start the same way: with a solid foundation, a real landing zone. Not a single VPC hastily assembled, but a structured AWS Organization designed to separate workloads and responsibilities for isolation, security, and manageability. This includes:

• Management account for centralized billing and orchestration
• Audit account for security monitoring
• Build account for CI/CD pipelines
• Log account to retain logs across all accounts for auditability
• Production account for live, customer-facing workloads
• Sandbox account for testing and development

This architecture enforces foundational security controls such as Service Control Policies (SCPs) and Identity and Access Management (IAM) configurations. It’s built for scalability and flexibility, allowing seamless addition of new accounts and services as business needs evolve.

Automation is critical. When your entire environment is deployed through CloudFormation or Terraform, you can trust its integrity. Without automation, you risk spending months chasing configuration drift you didn’t know existed.

Understand the System Before You Move Anything

Once the platform is in place, the next step is establishing the ground truth. Most legacy ArcGIS environments have grown organically. Services are scattered across servers. Databases sit on clusters that no one has patched in years. File shares hold rasters that only one person understands. Before you design a Kubernetes footprint or move a single dataset, you need to understand how the system really behaves.

AWS tools make large-scale migrations far more efficient. Services like DataSync move massive file repositories into EFS or S3 without months of manual effort. Database Migration Service, combined with Change Data Capture, keeps SQL Server geodatabases synchronized while legacy and cloud systems run in parallel. This parallel run isn’t optional, it’s essential. Every mission-critical migration relies on two environments for a transition period: the legacy system serving production and a Kubernetes-based ArcGIS Enterprise environment in AWS that gradually assumes responsibility as it proves stable.

Build the Right Architecture and Performance Follows

Stability starts with making the right architectural decisions early. Esri performance is highly dependent on the underlying AWS design. Running ArcGIS Enterprise on Kubernetes requires correctly sizing node groups, selecting appropriate storage classes, and knowing where EFS adds value, and where it doesn’t. For reliable database performance, use managed services like Amazon RDS or Aurora instead of manually maintaining SQL clusters on EC2. Finally, enable distributed logging from the start and route it through CloudWatch or an external SIEM to ensure full observability on day one.

This is also where AWS MAP becomes valuable. MAP is not a paperwork exercise. It forces the sequencing that avoids rework. Assess the environment with real numbers. Mobilize by closing readiness gaps. Then migrate and modernize with automation, guardrails, and repeatable infrastructure. MAP funding often offsets part of the effort, but the real benefit is structure and speed.

Compliance and Governance Are Built Into the Platform

Compliance is usually the next concern for agencies and regulated industries. AWS-native controls make this straightforward. With the right account structure, IAM patterns, encryption, centralized logging, and network segmentation, we can meet ISO 27001, NIST 800 53, and FedRAMP requirements as part of the base platform. Compliance is an outcome of the architecture, not a separate workstream you bolt on after the migration.

The Outcomes You Get When the Migration Is Done Correctly

When the modernization is executed correctly, the results are significant. We have seen 50 percent faster editing and geoprocessing, a 31 percent reduction in infrastructure cost, and a 50 percent reduction in infrastructure related incidents. New features ship faster, often 40 to 50 percent faster, because deployments are automated, environments are consistent, and the platform behaves predictably.

The biggest gain is integration. Once ArcGIS Enterprise runs in AWS, it connects seamlessly with ERP systems, CRM platforms, asset management suites, BI tools, IoT streams, analytics engines, and AI inference services. GIS stops being a silo and becomes part of the broader enterprise architecture. Location intelligence flows everywhere it is needed, not just inside GIS specific tools.

The Core Lesson From Every Large Esri Migration

The core lesson: the map is not the system. The surrounding architecture is. When you get the platform, the data paths, and the operational model right, the migration works. If you skip steps or patch problems as you go, those issues follow you into AWS and cost more to fix later. There is never a convenient moment to migrate a system this large, but waiting only adds complexity and risk. The work does not get easier with time.