Move mailboxes between on-premises and Exchange Online organizations in hybrid deployments
With an Exchange-based hybrid deployment, you can choose to either move on-premises Exchange mailboxes to the Exchange Online organization or move Exchange Online mailboxes to the Exchange organization. When you move mailboxes between the on-premises and Exchange Online organizations, you use migration batches to perform the remote mailbox move request. This approach allows you to move existing mailboxes instead of creating new user mailboxes and importing user information. This approach is different than migrating user mailboxes from an on-premises Exchange organization to Exchange Online as part of a complete Exchange migration to the cloud. The mailbox moves discussed in this topic are part of administrative Exchange management in a longer-term coexistence relationship between on-premises Exchange and Exchange Online organizations.
Step 1: Create a migration endpoint
Prior to performing on-boarding and off-boarding remote move migrations in an Exchange hybrid deployment, we recommend that you create Exchange remote migration endpoints. The migration endpoint contains the connection settings for an on-premises Exchange server that is running the MRS proxy service, which is required to perform remote move migrations to and from Exchange Online.
For step-by-step procedures
Step 2: Enable the MRSProxy service
If the MRSProxy service isn’t already enabled for your on premises Exchange 2013 Client Access servers, follow these steps in the Exchange admin center (EAC):
1. Open the EAC, and then navigate to Servers > Virtual Directories.
2. Select the Client Access server, and then select the EWS virtual directory and click Edit