Office365 – Migration Framework


In my previous article, I talked about Why Office365 Migration matters and what are the key approaches and considerations. In this article, I will cover a high-level migration framework.

In my humble opinion – a Migration Framework is critical for any Office365 migration from Exchange organization. The focus of the framework I am detailing our is primarily around a methodology for integration, co-existence and migration of existing Microsoft Exchange organizations to Microsoft Exchange Online as part of Office 365.

It is imperative to note that irrespective of the Migration Approach and/or third-party tools in scope, a phased migration approach for every customer irrespective of the size and complexity of the organization’s messaging infrastructure is what I recommend.

The phased migration approach allows for an identified exit criteria for each phase with review and approval (as necessary), while improving the predictability and consistency of the deliverables for the customer. This helps in setting the customer expectation for each phase with clear communication lines, project tracking and reporting.

The process that I follow for any Office365 Migration is structured around 5 key phases:

  • Analysis – that is focussed on discovery of infrastructure, business requirements & analysis. Key in deciding the scope and approach to be followed
  • Design – focussed on Solution Architecture & Migration Strategy aligned to timelines
  • Pre-Migration – Ensure all processes and prerequisites are in place to eliminate last minutes surprises
  • Migration/Co-existence – Actual transition from existing Microsoft Exchange on-premises environment to Exchange Online.
  • Post Migration – on-going training & support, leading to steady state.

A modular approach to the Migration Framework allows bundling of work into separate stages. While the above image provides a logical order in which these stages occur; this does not necessarily mean each stage must be complete before the next can start and in majority of cases they will most likely occur in parallel. The following sections provide an overview of the phases.

Phase 1 – Analysis

This phase is about discovering as much information as possible about the existing on-premises Exchange environment around Business requirement & Technical infrastructure like directory services, integrations, associated infrastructure like network, security, application and business users etc. This phase involves multiple meetings & discussions with Business Users & IT teams followed by workshops to demonstrate and validate the understanding of the customer environment

Phase 2 – Design

This phase would take the information that was gathered during the analysis stage to determine exactly what needs to happen for migration to the new environment.   This involves holding workshops with the required stakeholders and developing a detailed migration. The key deliverables would be a High Level Architecture, Migration Plan, Risk Registers, Traceability Matrix, Communication & Training Plans, BOMs etc.

Phase 3 – Pre-Migration

Before the migration phases can take place, there are a series of pre-migration steps that need to be configured on-premises infrastructure and Office 365. This phase is all about putting the plans in action to prepare the environments – technical, process and people readiness etc. Readiness of partner ecosystem is ultra-critical too.

Phase 4 – Migration / Coexistence

This phase is about actual migration, aligned to migration batches, user communication, all configurations, monitoring, configurations to name a few. Hyper care support etc.

Phase 5 – Post Migration

After a successful migration of all Messaging Data from on-premises Microsoft Exchange infrastructure to Office 365 organization will be followed by a clean-up of the existing messaging environments. Another round of training for Helpdesk and Support staff along with continued communication to users on features, FAQs, tips etc, followed by final decommission existing Exchange infrastructure. Finally, the Sign Off.

Hope this gives you are good understanding of how Office365 migrations need to be planned and executed. It is not only about technology but the process surrounding it.

Happy Migrations!