Reduce cutover risk
Run discovery, pilot migrations, dry-runs, and incremental synchronization before the final switch so production users are not the first test.
Vianordis--:--:-- UTCVianordis / ED. 02 / 2026
§ 07 — App support
O365 Migrator
Reclaim Microsoft 365 data without turning migration into a blind cutover.
O365 Migrator gives European organizations a controlled path from Microsoft 365 to Vianordis, with inventory, dry-runs, incremental synchronization, progress tracking, and validation before users are moved.
01 — Problem
Leaving Microsoft 365 is usually treated as a technical event, but the risk is operational.
Organizations want lower dependency, stronger data residency, and more control over collaboration data. The hard part is proving what exists, mapping users correctly, running a pilot, keeping users productive during pre-sync, and showing that the cutover finished cleanly.
- Tenant data is spread across identity, mail, calendars, contacts, tasks, OneDrive, SharePoint, and Teams.
- Administrators often lack a reliable inventory before committing to dates, scope, and budget.
- Manual exports create gaps, duplicate work, and weak evidence for compliance teams.
- Big-bang migration windows increase user disruption and rollback pressure.
- Source and target accounts, groups, permissions, and workload limits must be validated before production cutover.
- Leadership needs clear progress reporting instead of migration status hidden in scripts and logs.
02 — Solution
O365 Migrator turns cloud exit into a governed migration workflow.
The platform connects to Microsoft 365 through Graph APIs, maps users and tenants into the Vianordis target environment, validates the migration plan with dry-runs, then runs full or incremental jobs with tracked progress, retries, and reports.
- Inventory collection shows users, groups, mailboxes, calendars, contacts, tasks, files, Teams files, and SharePoint content before migration begins.
- Dry-run simulation identifies missing target accounts, permission gaps, size limits, naming conflicts, and workload risks before users are affected.
- Migration jobs move data into open and sovereign services such as FreeIPA, Dovecot IMAP, sabre/dav CalDAV/CardDAV, PostgreSQL-backed tasks, and Vianordis file services.
- Operators can track job status, item counts, failures, skipped records, elapsed time, and estimated remaining time through API and metrics.
03 — Benefits
Business outcomes before migration mechanics.
O365 Migrator is built for teams that need to reduce dependency on Microsoft 365 without accepting a fragile, opaque, or one-way migration process.
Stay in control of data
Move collaboration data into Vianordis services operated under a European infrastructure model with open protocols and tenant-aware controls.
Make scope visible
Use inventory reports to understand users, mail volume, calendars, contacts, tasks, files, SharePoint libraries, and Teams file content before pricing or scheduling.
Preserve portability
Support Microsoft 365 to Vianordis, Vianordis to Microsoft 365, and Microsoft tenant-to-tenant scenarios instead of locking migration into one direction.
Give stakeholders evidence
Expose job progress, item totals, failures, skipped records, warnings, and validation results so IT, compliance, and management can review the same facts.
Automate repeatable work
Use configured batches, retry logic, sync state, scheduled runs, and REST endpoints instead of ad hoc scripts for each migration wave.
04 — How it works
From tenant discovery to verified cutover in three steps.
- 01
Discover and map
Connect the Microsoft 365 tenant, collect workload inventory, define source-to-target user mappings, and confirm that target accounts and services are ready.
- 02
Simulate and pre-sync
Run dry-runs to find blockers, then start full and incremental migration jobs while users continue working in the source tenant.
- 03
Cut over and report
Run the final delta sync, switch users to Vianordis services, verify item counts and errors, and keep reports for operational and compliance review.
05 — Features
What administrators can actually do with O365 Migrator.
Tenant and user inventory
Collect identity, mail, calendar, contacts, tasks, OneDrive, Teams, and SharePoint inventory to size the migration before committing to a rollout plan.
Workload migration
Move identity records, mailboxes, calendars, address books, tasks, personal files, Teams files, and SharePoint documents into Vianordis target services.
Dry-run validation
Simulate migration by user and workload to find missing permissions, unsupported data, conflicts, size issues, and target-account gaps before writing data.
Incremental synchronization
Persist sync state and delta tokens so migration waves can be resumed, repeated, and kept current until the final cutover window.
Job and progress API
Create migration jobs, query status, inspect progress, and expose migration metrics through role-protected REST endpoints.
Batching, retry, and error handling
Use configurable batch sizes, retry logic, item-level status, structured errors, and skipped-item tracking to keep large migrations manageable.
06 — Architecture
Architecture and security model.
O365 Migrator separates source access, target services, migration state, API control, and operational reporting so migration can be planned, audited, and repeated.
- Microsoft Graph services read identity, mail, calendar, contacts, tasks, OneDrive, Teams, and SharePoint data from the source tenant.
- FastAPI exposes health checks, readiness checks, migration jobs, progress, and Prometheus metrics for operators and automation.
- JWT role checks protect read, write, and admin API paths for migration operations.
- PostgreSQL stores tenant configurations, user mappings, migration jobs, migration tasks, sync states, and migrated item records.
- Migration workers use dry-run mode, retry logic, batch controls, cancellation checks, and persisted sync state for repeatable execution.
- Vianordis targets include FreeIPA LDAP, Dovecot IMAP, sabre/dav CalDAV/CardDAV, PostgreSQL task storage, and the Vianordis file platform.
- Kubernetes deployment, structured JSON logging, non-root containers, readiness endpoints, and Prometheus metrics support production operations.
07 — Use cases
Where O365 Migrator fits.
Microsoft 365 cloud exit
Move collaboration workloads from Microsoft 365 into Vianordis when sovereignty, cost control, or platform strategy requires a European target.
Regulated organization migration
Give security and compliance teams inventory, validation, role-controlled access, progress records, and verification data for sensitive migrations.
Tenant consolidation
Map users and workloads across tenants after mergers, acquisitions, reorganizations, or domain changes.
Department pilot
Migrate one group, department, or pilot cohort first, validate user experience, then expand with the same workflow.
Return or portability migration
Preserve flexibility with Microsoft 365 to Vianordis, Vianordis to Microsoft 365, and Microsoft tenant-to-tenant directions.
08 — Integrations
Connects to the systems that define a Microsoft 365 migration.
O365 Migrator is built around standard APIs and open target services so administrators can reason about the path from source tenant to sovereign environment.
Microsoft Graph
Shows how this service fits into the wider Vianordis environment instead of standing alone.
Entra ID
Shows how this service fits into the wider Vianordis environment instead of standing alone.
Exchange Online
Shows how this service fits into the wider Vianordis environment instead of standing alone.
Outlook Calendar
Connects scheduling data so time, meetings, and availability stay part of the workflow.
Outlook Contacts
Connects address-book data so people and organizations remain visible in context.
Microsoft To Do
Shows how this service fits into the wider Vianordis environment instead of standing alone.
OneDrive
Shows how this service fits into the wider Vianordis environment instead of standing alone.
SharePoint
Shows how this service fits into the wider Vianordis environment instead of standing alone.
Microsoft Teams
Shows how this service fits into the wider Vianordis environment instead of standing alone.
FreeIPA / LDAP
Shows how this service fits into the wider Vianordis environment instead of standing alone.
Keycloak
Keeps access tied to organization accounts, roles, and sign-in policy.
Dovecot IMAP
Connects communication records so messages can be used in the governed workflow.
sabre/dav CalDAV
Connects scheduling data so time, meetings, and availability stay part of the workflow.
sabre/dav CardDAV
Connects address-book data so people and organizations remain visible in context.
PostgreSQL
Stores structured service records in a controlled tenant-aware backend.
Vianordis file services
Shows how this service fits into the wider Vianordis environment instead of standing alone.
Prometheus
Shows how this service fits into the wider Vianordis environment instead of standing alone.
Kubernetes
Shows how this service fits into the wider Vianordis environment instead of standing alone.
09 — Trust
Compliance and trust signals.
O365 Migrator is designed so administrators can explain where data moves, who can operate migrations, how progress is tracked, and how exceptions are reviewed.
Source control
Microsoft 365 access uses configured tenant credentials and Graph API permissions rather than uncontrolled user exports.
Target residency
Migration targets are Vianordis services operated under the platform's European infrastructure model.
Identity governance
FreeIPA LDAP and Keycloak integration keep target accounts, authentication, and service authorization under central control.
Operational evidence
Jobs record status, user progress, item totals, failures, skipped items, errors, warnings, timestamps, and sync state.
API protection
Read, write, and admin operations are protected through JWT roles such as migration:read, migration:write, and migration:admin.
Production posture
Kubernetes manifests, readiness checks, non-root containers, structured logs, and Prometheus metrics support controlled operation.
10 — Pricing
Use published migration pricing or scope a migration in a demo.
O365 Migrator is listed on the Vianordis rate card. For production migrations, a demo is the fastest way to review tenant size, workloads, pilot groups, target readiness, cutover windows, and support requirements.
11 — FAQ
Questions technical buyers usually ask.
Who is O365 Migrator for?
O365 Migrator is for organizations planning to move Microsoft 365 collaboration data into Vianordis, consolidate tenants, run a phased pilot, or preserve a return migration path.
What data can be migrated?
The platform targets identity, email, calendars, contacts, tasks, OneDrive files, Teams files, and SharePoint documents. Some Microsoft 365 objects may require export-only handling or manual rebuild depending on API support and target capabilities.
Does it create target users automatically?
Target users should exist in FreeIPA LDAP before migration. The migrator validates mappings and moves workload data into the prepared target services.
Can we run a dry-run first?
Yes. Dry-run simulation is a core workflow. It estimates scope and highlights missing permissions, missing target accounts, conflicts, limits, and other issues before data is written.
How is progress tracked?
Migration jobs expose status, current user, workload, item totals, migrated items, failed items, skipped items, elapsed time, estimated remaining time, errors, and Prometheus metrics.
Can migration be phased?
Yes. Administrators can migrate selected users, groups, workloads, or tenants, then use incremental synchronization until the final cutover window.
Can it migrate back to Microsoft 365?
The data model supports Microsoft 365 to Vianordis, Vianordis to Microsoft 365, and Microsoft tenant-to-tenant directions, subject to configured services, permissions, and target readiness.
12 — Next step
Move from Microsoft 365 with inventory, validation, and evidence instead of guesswork.
See how O365 Migrator can scope your tenant, validate target readiness, pre-sync workloads, and support a controlled cutover into sovereign Vianordis services.