Now, what if your organization has lots of mailboxes? You will be headed towards Cutover Migration which will provide you the option of migration of all the users from Exchange Server to Office 365 at once. Unfortunately, this will lead you and your organization to reconfigure all the outlook profiles after the migration is done with. This choice is not recommended if your clients require selective and seamless migration for their users as there is no option to selectively migrate on-premise Exchange Server objects.
Hybrid configuration comes to rescue to overcome the limitations of staged and cutover migration. However, this approach has strict prerequisites for certificates and other confusing and unnecessary configuration settings. Well, there’s a better option available i.e. Minimal Hybrid Configuration.
Minimal Hybrid Configuration
This solves all the problems of staged and cutover migration. Introduced by Microsoft in 2016, Minimal Hybrid Configuration sometimes known as express migration helps in providing improved and simplified migration process. As it allows just a subset of features of Full- Hybrid Migration according to the needs of clients such as enabling mailbox migration from Exchange Server to Office 365 without the needless administrative efforts. Using Minimal Hybrid configuration, clients get to keep directory synchronization in place and move all their mailboxes to Exchange Online in a short amount of time. As it is a one-time sync process for all users present on Exchange server to Office 365, it provides migrating mailboxes with minimal disruption.
Note: Minimal Hybrid Configuration can be used only if you have never performed a Full Hybrid deployment. The Minimal Hybrid option will not be present if Full Hybrid Configuration is used before for that client.
Some features are excluded from the Minimal Hybrid configuration and these are listed below:
- Cross-premises Free/Busy sharing.
- ActiveSync, Outlook Web Application(OWA), and Outlook Anywhere redirection for migrated users.
- TLS secured mail flow between on-premises Exchange Server and Office 365.
- Cross-premises eDiscovery.
- Archive mailbox automatic retention.Here, we discuss the six main steps in detail involved in the Minimal Hybrid Configuration. The steps are as follows:6 Steps to Migrate from Exchange Server to Office 365 using Minimal Hybrid Configuration.
Step 1: Verify that the Domain is owned by you.
As per the first step add and verify the domain in your Office 365 tenant. Since email addresses for the users need to be created in the Office 365 environment, the on-premises domain must be added and verified before the migration process can be initiated.
Follow these steps:
1. Sign in with your work or school Office 365 account.
2. Head to the Settings and select Domains.
3. On the Domains page, click Add domain to start the domain wizard.
4. Type in the domain name (e.g., contoso.com) you use for your on-premises Exchange organization and click Next.
5. Select TXT record for domain verification. It is typically chosen to verify ownership.
6. After adding your TXT, wait for 15 minutes approximately before proceeding to the next step.
7. In the Office 365 domain wizard, click Done and then Verify Now, and a verification page will appear.
8. Now, choose I’ll manage my own DNS records and do not progress to the next step in the domain wizard.
Step 2: Initiate the Minimal Migration
To Initiate the Exchange Server to Office 365 migration, you are required to sign in to your Office 365 account using global admin credentials on an on-premises domain joined desktop computer of your organization. Once you’re signed in, head to the Data migration page of the Office 365 admin center to open the Exchange Hybrid Configuration Wizard.
Follow these steps:
1. In the admin center of Office 365, under the drop-down menu go to Setup and then select Data migration.
2. On the Data Migration page, under Select your data service, choose Exchange.
3. Click on Download application to download and run the Office 365 Hybrid Configuration Wizard.
4. A welcome screen of the Hybrid Configuration Wizard page will be shown, Click Next.
5. On the On-premises Exchange Server Organization page, do not change any value and let them as they are, and click Next. By default, the wizard connects to Exchange Server.
6. Provide your credentials for both Exchange On-premises and Exchange Online on the Credentials page and click Next for validating the credentials.
7. On the Hybrid Features page, select Minimal Hybrid Configuration, and click Next.
8. Click update on the Ready for Update page, to prepare the on-premises mailboxes for Exchange Server to Office 365 migration.
Step 3: User Provisioning
1. On the User Provisioning page, select the Synchronize my users and passwords one-time (Recommended) option, and click Next.
2. Now, a prompt to download and install the Azure AD Connect wizard will appear for synchronizing users from on-premises to Office 365.
3. Once it is downloaded and installed, run the Azure AD Connect, and choose the default options for Express settings.
After synchronization is over, you will be directed to the Office 365 Data migration page, where all the users can be seen who were synchronized to Office 365. As this a one-time sync process it will be turned off for your Office 365 tenant.
Step 4: Assign Office 365 Licenses to Users
After users and their passwords are synchronized by Azure AD Connect to Office 365, you’ll need to assign Office 365 licenses to the users so that they are assigned cloud mailboxes to which their on-premises mailbox data will be migrated. Data migration page shows status of each mailbox indicating that a license is required, as shown in the figure below.
In the admin center, go to Users, and select Active users. Assign licenses to your users.
Step 5: Start Migrating User Mailboxes
After licenses to users are assigned, you can start migrating mailboxes from the Data migration page.
Follow these steps:
1. Go to Setup -> Data migration. Choose “Exchange”.
2. On the Data migration page, select the users whose mailboxes you wish to migrate, and click Start Migration.
Do migrate some test mailboxes from Exchange Server to Office 365 before migrating all mailboxes to ensure that everything is working properly.
The Data migration page shows the migration status as the migration progresses.
Step 6: Update Public DNS Records
For pointing all your new emails to Office 365, you need to update MX records to point to Office 365. Once your email migration is complete and all your mailboxes have been migrated to Office 365, you will also need to finish setting up your other DNS records, such as CNAME, TXT, and SRV.
Benefits of Hybrid Configuration for Exchange server to Office 365 migration
The Minimal Hybrid Configuration provides many benefits and features, including the ability to migrate online mailboxes without recreation of Outlook profiles; the ability to synchronize user account credentials; the option to exclude configurations of secure email; and Exchange Federation related features, such as Free/Busy, eDiscovery, and more. Now, you can easily access your mailboxes on the go after successful Exchange Server to Office 365 Migration.