Office 365 Things You Need To Know: Migration Decision Factors

Blog 2
Jeff Stoffel

Exchange Online is part of Office 365 and provides a cloud-based messaging solution.  Today we are going to talk about the decision factors you need to uncover in order to plan a migration strategy for your customer.

There are many paths to migrate data from an on-premises email organization to Office 365 Exchange Online. When planning a migration to Exchange Online, a common question is about how to improve the performance of data migration and optimize migration velocity.  Many decision factors come into play when determining the migration path and highlight the importance of up front planning.

The following items need to be discovered and evaluated in order to pull together a migration strategy and deployment plan:

Size – the number of mailboxes as well as size of mailboxes should be investigated.  It is quite possible to migrate using a PST export/import however this may not make sense for anything over a few mailboxes.  Size will also impact migration timelines and in turn impact coexistence requirements.

Coexistence – what level of coexistence do you need during the migration process?  If the entire migration takes place over a weekend this may be a very simple decision factor.  Often however you will have a period of time during the migration where you need to coexist.  The customer desires and expectations for the coexistence period will impact the strategy.

Provisioning – how do you plan to provision the user accounts?  Are you planning to leverage a synchronization tool or are you provisioning with an import.  Is the organization small enough planningyou plan to manually create new accounts?

Migration Source – what you are migrating from can have a huge impact on your migration plans.  Is the source Exchange, IMAP, or other email solution?  Do you need to migrate calendar information and contacts?  The migration source can greatly impact the ease of which these items can be migrated.

Identity Management – you need to determine the approach for identity management.  Is single sign-on a requirement?  Will identities exist in the cloud only or do we need to connect with an on-premises identity source.

Now that you have went through gathering the decision factors you are ready to put together your migration strategy.  I’ll post about a few different migration methods later in the week.  You can then use your decision factors to determine which method makes the most sense for your customer.

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