Rafael Pfister

Consulting

Exchange Online migration: controlled instead of big bang

The end of support for the old Exchange versions is decided, the direction is Exchange Online; what remains open is the route. I support migrations from routing design to the shutdown of the last on-premises server, including the edge cases the hybrid wizard has no answer for.

  • Exchange Online
  • Mailbox Migration
  • Hybrid
  • Mail Routing
  • Gateway Integration
  • On-Prem Decommissioning

What a mail migration really covers

Moving mailboxes is the smallest part. What has to be decided is how the MX moves, what happens to the upstream gateway, which applications and devices keep submitting over SMTP, how SPF, DKIM and DMARC survive the move, and when the on-premises estate can truly be shut down. Answering these questions during the migration means migrating twice.

Services

  • Migration designTarget architecture, routing phases and sequence; hybrid as a transition or as a permanent state, decided deliberately.
  • Mailbox migrationBatches, communication and follow-up work; including the controlled rebuild without remote move when the standard route is blocked.
  • Application and device mailPrinters, scanners, business applications: inventory them, move them to authenticated submission, eliminate the direct-send leftovers.
  • Gateway and DNS moveFitting encryption gateways into the new route, MX cutover and authentication records without a delivery gap.

How an engagement runs

  1. InventoryMailboxes, submitting systems, routing and dependencies; the inventory decides the migration route.
  2. PilotA small, representative group first; the findings feed the plan for everyone else.
  3. Migration in wavesBatches with defined checkpoints, routing changes one at a time and reversible.
  4. CompletionOn-premises decommissioning, documentation of the target environment, handover to operations.

Real-world examples