Edwin009 -> RE: Cutover or Stage migration or Hybrid -option (8.May2020 6:59:07 AM)
When you're deciding on a migration method, you should consider the following factors:
The number of objects to be migrated
The amount of data to be migrated
Your existing email system
Your Exchange Servers version
The duration of the migration project
The costs involved
It's important to have these details nailed down before you start migrating data. After you're clear on the basics, you can move on to choosing a migration method.
This section describes various email migration methods that you might want to consider.
A cutover migration migrates all existing mailboxes, contacts, and distribution groups from an on-premises Microsoft Exchange system to Office 365.
This type of migration is performed as a single batch move that includes all of your mailboxes, contacts, and distribution group objects. There's no option to migrate objects selectively. After the migration is complete, every user that has an on-premises Exchange mailbox also has an Office 365 account.
When to choose a cutover migration
You might want to choose a cutover migration when the following conditions are met:
The current on-premises Exchange environment is Exchange 2003, 2007, 2010, or 2013.
The current on-premises Hosted Exchange Hosting environment has less than 2,000 mailboxes.
A staged migration migrates all existing users and resource mailboxes from on-premises Exchange 2003 and Exchange 2007 organizations to Exchange Online.
This migration method moves mailboxes to Office 365 over a period of time. When the process is complete, all mailboxes are hosted in Office 365. This option is suitable for medium-sized organizations.
When to choose a staged migration
You might want to choose a staged migration when the following condition is met:
The source email system is Microsoft Exchange 2003 or 2007.
With a hybrid deployment, you can integrate Office 365 with your on-premises Exchange servers, and also with the existing directory services. This functionality facilitates the synchronization and management of user accounts for both environments.
Hybrid deployments provide rich features
A hybrid configuration wizard establishes federation and connectors between an on-premises Exchange environment and an Office 365 tenant.
With hybrid deployments, mailboxes can be natively moved in and out of Exchange Online. It's also possible to keep some mailboxes on-premises and some on Office 365.
You can also add password synchronization or single sign-on (SSO) so that users can log on to both the environments with their on-premises credentials.
When to choose hybrid deployments
You might want to choose a hybrid migration when the following condition is met:
The source email system is Exchange 2010 or later. Learn more abot Hybrid Office 365 Migration and Hosted Exchange Migration to Office 365