Migrate User Mailboxes in Batches to Office 365 by Using the Hybrid Migration Method

This article explains how to reconfigure Riva On-Premise 2.4.37 or higher to migrate user mailboxes in multiple batches of users from Exchange on-premises to Office 365 by using the Microsoft hybrid migration method.

Contents:

• When to use this procedure,
• How to schedule Riva Professional Services to assist with this procedure,
• Migration scenario, and
• Riva procedure to migrate user maiboxes to Office 365 by using hybrid migration.

When to Use This Procedure

This procedure can be used if the following conditions are met:

• Mailboxes will be migrated from on-premises Exchange to Office 365 by using the AD-integrated hybrid migration procedure;
• Users are assigned to the Riva sync policy by using one or more Exchange-enabled distribution groups;
• The plan is to migrate mailboxes in batches of users to Office 365, so that Riva needs to continue syncing mailboxes located in both systems at the same time.

Note: This procedure requires Riva 2.4.37 or higher. Before proceeding, determine which version of Riva is installed and upgrade Riva to the latest public release if required.

How to Schedule Riva Professional Services to Assist with this Procedure

To request professional services to lead your Riva admin team through this procedure, contact the Riva Success Team.

Migration Scenario

This procedure was developed for a client who originally assigned 120 users to a Riva sync policy by using a group we will call RivaSyncUsers@example.com. They planned to migrate users in batches of 20 users from on-premises Exchange to Office 365 by using the Microsoft hybrid migration tools and procedures. The end state was to have all Riva-synced users assigned to the sync policy by using a single Exchange enabled group in Office 365. This client had a migration plan that identified which batch the users would be migrated in. Each batch would be referred to as a "Wave"; hence, there are six waves: Wave 1 to Wave 6 inclusively.

Riva Procedure

To migrate batches of user mailboxes by using hybrid migration:

1. Perform a "Migration" test to confirm that Exchange IDs will not change.
2. Prepare Office 365.
3. Prepare Exchange on-premises.
4. Modify the user assignment groups in the Riva sync policy.
5. Migrate a wave of users to Office 365.
6. Clean up in Riva after all users have been migrated.

Step 1: Perform a "Migration" test to confirm that Exchange IDs will not change

We highly recommend that the Riva Admin conduct a Migration connection test against a test mailbox to confirm that FolderIDs do not change when a user mailbox is migrated by using the exact procedure that will be used when production mailboxes are migrated. If the Migration test reveals that FolderIDs do change during the mailbox migration, contact the Riva Success Team.

This test requires migrating a test mailbox from Exchange on-premises to Office 365 by using the exact procedure that will be used to migrate production mailboxes. This mailbox does not need to be synced by Riva. This mailbox does need to be active, and it does need at least one item for each module type that Riva will sync (for example, one contact, one task, one calendar item, and one email (sent or received)).

To perform Migration Test & Compare:

1. Prepare a test mailbox that has been logged into by using Outlook Web Access (OWA) or Outlook and that has at least one of each type of item created.

2. Open the Riva Manager application. On the menu, under Connections, select Add Email. (In older versions of Riva, on the menu, select Setup.) Create an EWS connection, and use the credentials of the test user mailbox.

3. Run a Migration Test and Save procedure against the test user mailbox. (See Test upgrading an Exchange mailbox in the Riva EWS connection, steps 1 to 7.)

4. Migrate the test user mailbox to Office 365 by using the exact procedure that will be used for production mailboxes. Confirm that the mailbox migration was successful by logging in to the mailbox in Office 365 OWA.

5. In the Riva Manager application, if the menu displays Setup, select Setup. On the right pane, double-click the new EWS connection that is used for the test user mailbox.

6. In the EWS Connection Edit window, on the Connection Details page, change the Host URL to https://outlook.office365.com/EWS/Exchange.asmx, so as to switch the connection to use Office 365. Save the connection.

7. On the right pane, double-click the EWS connection that is used for the test user mailbox.

8. Run a Migration Test and Save procedure against the test user mailbox. (See Test upgrading an Exchange mailbox in the Riva EWS connection, steps 10 and 11.)

   If the FolderIDs remain unchanged, you can use the rest of the procedure described in steps 2 to 6 below.
   
   If the FolderIDs have changed, contact the Riva Success Team for assistance to configure Riva to support your user mailbox migration plan.

9. Close the test result screens. Close the EWS connection edit window.

Step 2: Prepare Office 365

To prepare Office 365 for Riva and the Windows host server for connectivity to Office 365:

1. Create a service user account in Office 365 that has a fully enabled mailbox and that is visible in the GAL.

2. Create a new Exchange-enabled group in Office 365 that migrated users will be added to, for example RivaSyncUsersO365@example.com.

3. Assign Exchange ApplicationImpersonation Role permissions to the service user over the user mailboxes in the RivaSyncUsers group, for example RivaSyncUsersO365@example.com.

4. Prepare corporate firewalls for connectivity with Office 365.

5. Confirm connectivity from the Windows host server to Office 365.

6. Open the Riva Manager application. On the menu bar, under Connections, select Add Email. (In older versions of Riva, on the menu, select Setup.) Create a new EWS connection by using the credentials of the new service account in Office 365. Ensure that Impersonation method is set to EWS Impersonation.

7. Perform a connection test and an impersonation test by using the test mailbox that was migrated to Office 365 at Step 1: Perform the Migration Test & Compare test.

8. Remove the test mailbox from the RivaSyncUsers group.

Step 3: Prepare Exchange on-premises

The idea is to create Exchange-enabled groups for each wave of Riva-synced users that will be migrated and add the users to the membership list for their corresponding group. For this example scenario, create the following groups, and add the applicable Riva-synced users as members:

• RivaSyncUsersWave1@example.com,
• RivaSyncUsersWave2@example.com,
• RivaSyncUsersWave3@example.com,
• RivaSyncUsersWave4@example.com,
• RivaSyncUsersWave5@example.com, and
• RivaSyncUsersWave6@example.com.

Step 4: Modify the user assignment groups in the Riva sync policy

The idea is to modify the user assignments in the Riva sync policy to use the new wave groups instead of the single group originally used.

To use the new wave groups:

1. In the Riva Service Monitor application, stop the service.

2. Open the Riva Manager application. On the menu, select Policies. Double-click the sync policy to edit it.

3. Remove the original group that assigns all the users to the sync policy. (In this example scenario, remove the RivaSyncUsers@example.com group.)

4. Add the new wave groups to the sync policy. (In this scenario, add the RivaSyncUsersWave1@example.com to the RivaSyncUsersWave6@example.com groups.)

5. Add the Office 365 Riva SyncUser group to the sync policy; for example, add the RivaSyncUsersO365@example.com group.

6. Save the sync policy, and when prompted, start the service.

7. In the Riva Service Monitor application, confirm that all users are syncing as expected.

Step 5: Migrate a wave of users to Office 365

To migrate each wave of users:

1. In the Riva Service Monitor application, stop the service.

2. Optional: Open the Riva Manager application. On the menu, select Policies. On the right pane, double-click the Exchange connection for on-premises Exchange. For each user being migrated to Office 365, perform a Migration Test & Save.

3. In the Riva Manager application, on the menu, select Policies. On the right pane, right-click the sync policy, and edit it.

4. Remove the RivaSyncUsersWave group for the users being migrated; for example, RivaSyncUsersWave1@example.com. Save the sync policy, and start the sync service to resume normal data sync for the remaining user mailboxes.

5. Migrate the user mailboxes to Office 365.

6. Confirm that all mailboxes migrated successfully.

7. Optional: Open the Riva Manager application. On the menu, select Policies. On the right pane, double-click the Exchange connection for Office 365. For each user mailbox that was migrated to Office 365 as part of that batch or wave, perform a Migration Test & Compare.

   If any user mailbox Migration Test & Compare tests show that FolderIDs did change for that user, ensure that you do not add that user to the RivaSyncUsers group in Office 365 (for example, RivaSyncUsersO365@example.com). Contact the Riva Success Team, and ask for assistance to add that user mailbox into a "Line-in-the-Sand" sync policy.
   
    

8. In Office 365, add the users to the RivaSyncUsers group; for example, RivaSyncUsersO365@example.com.

9. In the Riva Service Monitor application, restart the service to force Riva to reread the membership lists of the groups assigned to the sync policy.

   Result: Riva sees the additional users just added to the RivaSyncUsersO365@example.com group.

10. Confirm that Riva has resumed data sync for the users that were just migrated.

Step 6: Clean up in Riva after all users have been migrated

After all of the Riva-synced user mailboxes have been migrated and data sync has been restored, proceed as follows.

1. Open the Riva Manager application. If the menu displays Setup, select Setup. On the right pane, remove the original EWS connection to Exchange on-premises by right-clicking the connection and choosing Remove.

2. In Office 365, remove the target user mailbox that was originally used at Step 1: Migration Test and Compare Testing.