Exelon — Enterprise On-Premises to OneDrive Migration
A 45,000-user, 120TB migration executed inside Exelon's nuclear-regulated Fortune 100 environment — with MNPI compliance, dual-platform tooling, and zero data loss across nine months of nightly operations.
The largest compliance-sensitive OneDrive migration Summit has executed.
Exelon Corporation, one of America's largest energy utilities, required retirement of all legacy home directories and migration of 45,000 users to OneDrive for Business. The effort demanded MNPI compliance, after-hours execution, dual-platform tooling, and zero tolerance for business impact across nuclear-regulated operations.
Summit executed the full engagement over nine months — nightly waves, morning validation, zero incidents.
A Fortune 100 utility with decades of infrastructure debt.
Exelon operates nuclear, fossil, wind, and hydroelectric facilities nationwide. Tens of thousands of users stored data on aging NetApp systems with decades of permissions sprawl across a multi-domain Active Directory environment.
The mandate was clear: retire all legacy home directories, move every user to OneDrive, and do it without touching business operations.
Five constraints that shaped every decision.
MNPI Compliance
Material Non-Public Information requirements governed all migration activities — access controls, timing, and data handling had to satisfy regulatory requirements at every step.
Legacy Permissions Sprawl
Decades of accumulated permissions on NetApp systems required remediation before migration could proceed safely.
Multi-Domain Identity Complexity
Multiple Active Directory domains added identity mapping complexity across the 45,000-user population.
Network Throttling Risk
Migration traffic on a utility network required precise bandwidth controls to avoid impacting operational systems.
Edge-Case File Types
Access databases, OneNote packages, and PST files required specialized handling that single-platform tooling couldn't reliably manage.
Dual-platform architecture for throughput and reliability.
Summit deployed SkySync and Microsoft Migration Manager in parallel — enabling greater throughput, redundancy, and advanced handling of file types that no single platform could manage alone. The dual architecture also provided a failover path: if one platform encountered an edge case the other could handle it without interrupting the nightly wave schedule.
A repeatable nightly cycle across nine months.
- OneDrive provisioning via PowerShell scripting for each user wave
- Temporary admin access granted for migration window
- Nightly after-hours migration execution with real-time bandwidth tuning
- Morning validation — data fidelity checks and error remediation before business hours
- Admin access revocation and legacy directory decommission upon wave completion
Purpose-built stack for a regulated enterprise environment.
- SkySync — primary migration tooling for throughput and edge-case handling
- Microsoft Migration Manager — parallel tooling for redundancy and standard file types
- PowerShell automation — OneDrive provisioning and admin access management
- Microsoft Information Barriers — MNPI compliance enforcement
- OneDrive for Business — destination platform
Every user. Every byte. Zero incidents.
- 45,000 users migrated with zero data loss and zero business disruption
- 120TB transferred across nine months of nightly operations
- Legacy NetApp infrastructure fully retired
- All MNPI compliance requirements satisfied throughout
- No incidents reported across nuclear-regulated operations
- Dual-platform architecture validated for enterprise-scale regulated environments
What this engagement demonstrated.
Precision execution enables even the most regulated environments to modernize safely — without touching operations.
Dual-tool architecture maximizes throughput and handles edge cases that no single platform reliably manages.
Nightly operations models with morning validation eliminate business impact at any scale.
Compliance requirements don't slow a migration when they're engineered into the methodology from day one.