Four Azure Tenants. One Migration Window. Zero Surprises.
Three acquisitions. Three regional subsidiaries. Three Azure tenants, three Active Directory forests, three M365 environments — all separate, all independent, all under the same parent company’s balance sheet.
When the board set an 18-week integration deadline for a global asset management firm’s largest ever consolidation programme, the IT team had a question they couldn’t answer: what exactly are we merging?
What the Discovery Found
ACQI ran 124 discovery modules across all four environments in parallel. The results arrived in the first 72 hours.
Identities: 47,312 accounts across four AD forests. No master directory. Overlapping UPNs across forests — the same email domain used by three of the four subsidiaries simultaneously. 1,847 orphaned accounts flagged for immediate review.
Applications: 340 applications fingerprinted and classified. 12 undocumented legacy systems that weren’t on any asset register. 23 cross-tenant shared service dependencies — services in one tenant that applications in another tenant depended on.
Compliance: GDPR data residency violations in two of the four tenants. Conditional access policies in three tenants that referenced resources in the fourth. PIM assignments that spanned tenant boundaries.
Infrastructure: Three on-premises data centres. Two Azure regions. Four ExpressRoute connections. No documented dependency map for any of it.
The Four-Phase Approach
Phase 1 — Weeks 1–3: Discovery Sprint. ACQI running across all four environments simultaneously. Every identity catalogued, every application classified, every dependency mapped. Discovery data fed directly into the governance layer for risk scoring and migration planning.
Phase 2 — Weeks 3–5: Risk and Dependency Analysis. Cross-referencing discovery data to identify migration blockers. Four business-critical applications flagged as migration-blocking due to cross-tenant dependencies. 16 conditional access policies with scope conflicts. Full risk heatmap exported for executive sign-off before any migration work began.
Phase 3 — Weeks 5–8: Wave-Based Migration Planning. Discovery intelligence fed directly into the migration planner. 47,000+ identities sorted into six dependency-ordered waves. Go/No-Go gates defined at each wave boundary. Rollback procedures documented per wave using verified configuration baselines.
Phase 4 — Weeks 8–18: Execution. Six migration waves executed in sequence. Real-time monitoring in the governance layer. Every identity movement tracked. Synergy tracking running in parallel with integration milestones.
Results
Six waves. All completed on schedule. 99.7% cutover success rate across all users. Zero P1 incidents across all migration windows. Full audit trail captured for FCA compliance review.
The integration was delivered on the original board-mandated deadline. The team attributed it directly to having complete discovery data before the first migration window was booked.
ACQI is the M&A Discovery, Migration, and Governance platform. 124 modules. Zero blind spots. Learn more →