migrate mailboxes

Question

Our company, let’s say Contoso.com, is hosted on Microsoft 365. We have acquired another company, lets say Acquired.com, which is currently using Google Workspace.

We plan to migrate all mailboxes from Acquired.com (Google Workspace) to our Contoso.com Microsoft 365 tenant. Mailboxes have already been created in our M365 tenant; we just need to migrate mailbox data from Google Workspace to the corresponding Microsoft 365 mailboxes.

We intend to use Microsoft FastTrack services for the migration. I’ve created a FastTrack project and am currently working through the prerequisite setup.

So far, I have completed the following:

• Created a Google service account
• Generated the JSON key file
• Created the Google migration project
• Enabled the Gmail API
• Enabled domain-wide delegation for the service account

However, I’m currently stuck on the following steps outlined by Microsoft:

1. Configure Forwarding Domain

https://learn.microsoft.com/en-us/Exchange/mailbox-migration/perform-g-suite-migration#create-a-subdomain-for-mail-routing-to-microsoft-365-or-office-365

Question: Do I need to add my domain (contoso.com) to the Google Workspace Admin Console, and then configure forwarding from each Google Workspace mailbox to the corresponding Microsoft 365 mailbox? Reference: https://learn.microsoft.com/en-us/Exchange/mailbox-migration/google-workspace-migration-prerequisites

2. Configure Migration Endpoint in Exchange Online. (Do i need to create any endpoint in M365, i am not clear here.)

https://learn.microsoft.com/en-us/Exchange/mailbox-migration/perform-g-suite-migration#start-a-google-workspace-migration-batch-with-the-new-exchange-admin-center-new-eac

3. Validate the Migration Endpoint.( i am not clear what changes do i need to make on M365 side)

https://learn.microsoft.com/en-us/powershell/module/exchange/get-migrationendpoint?view=exchange-ps

4. Provide Migration Credentials

I’m being prompted to “Add your credentials now.”

Do I need to create three accounts in Entra ID (formerly Azure AD)?

If yes, what are their roles or permission requirements?

• Or is it referring to the Google Workspace service account credentials used for the migration endpoint?

Answer 1

Hi Rising Flight,

Thank you for posting your question in the Microsoft Q&A forum.

 Since Acquired.com is the primary domain in your google workspace, the subdomain o365.acquired.com should be used for mail routing to O365 instead of the new domain contoso.com.

A migration endpoint is required to be created before the migration, and the super admin within the Google Workspace environment will be used. You can check this part for more details about migration endpoint:

Create a migration endpoint in Microsoft 365 or Office 365

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