Watchpoints & best practices

Google Workspace to Google Workspace migration

Before you begin a Google Workspace to Google Workspace migration, make sure to review Google Workspace Migrate best practices. Then, familiarize yourself with the following points.

Gmail  |  Calendar  |  Drive


Watchpoint Best practices
Email forwarding—To avoid duplicates and errors, email messages are checked to make sure they don’t exist in the target mailbox.

If you use email forwarding and turn on Accelerate Old Messages in the settings template, you’re likely to get some data duplication.

If you turn on Accelerate Old Messages with email forwarding, set Insert Before Date field date to the day before forwarding was turned on. Doing so reduces the risk of data duplication. For more details, go to Understand scan reports.

Links in email messages might be crawled by Gmail during a migration.

Gmail scans migrated email messages for security and threat issues. In some cases, Gmail crawls links included in the body of email messages.

You can avoid this issue by using the Accelerate old messages option in your settings template. Before you use the setting, make sure you’re fully aware of how it works. For details, go to Understand Exchange settings templates.

Changing a user’s email address.

Once you start migrating a user’s content, we recommend that you don’t change their email address.

If you change an address during or after a migration and then run a delta migration, Google Workspace Migrate remigrates all of the user’s content, which makes the process significantly slower than usual.


Watchpoint Best practices
Calendar migrations–API limits

If you’re running a large migration (1,000+ calendars), you might reach the Google Calendar API daily limit and see 403 errors. You can request an increase to the daily limit for the Calendar API.

Run a scan to get the total number of events you need to migrate. Then, determine how many events you're likely to migrate in a 24-hour period and request a Calendar API quota of 3 times that amount. For more details, go to Requesting higher quota.
Calendar resources–Identity mapping Make sure you map calendar resources in an identity mapping. For more details, go to Create and manage an identity mapping.
Calendar resources–Autoaccept meetings

If the calendar resource is set to Auto-accept meetings that don't conflict (the default), and conflicting bookings are migrated, the meeting organizer receives an email for each declined invitation. The super administrator also receives an email. Go to Calendar resources–super administrator accounts.

You can use content compliance rules to deliver these messages to email quarantines. For more details, go to Set up rules for content compliance.

Calendar resources–Super administrator accounts By default, Google Workspace Migrate uses all super administrator accounts to write calendar resource events to the target domain. Using super admin accounts increases migration speed and reduces the risk of quota issues.

Before you begin:

Following a migration:

  • If the calendar resource is set to Auto-accept meetings that don't conflict, the default and conflicting bookings are migrated, the super admin (and the organizer) receives an email notification for all declined invitations. You can use content compliance rules to deliver these messages to email quarantines. For more details, go to Set up rules for content compliance.
  • In the resource's calendar, the event shows as “Created by” the super admin. The activity is tracked in the Calendar audit log.


Watchpoint Best practices
Large single user migrations—A migration of 50,000 files or more to a single user’s Drive requires extra planning.

Use a sharding users list to spread the migration load among many user accounts.

To determine the number of user accounts to add to the list, use the larger value of:

  • One account for every 50,000 files that are being migrated to Drive
  • 10 accounts for each node
We recommend you set up temporary Google Workspace users for your sharding users list. Then, delete the users after you complete the migration. For more details, go to Create a sharding users list.
Comments in Google Docs files—The system copies comments along with the files.

Following a migration: 

  • Copied comments and comments that mention a user (using @email-address in the comment) remain associated with the original users on the source account. 
  • The system adds a note that the comments were copied.
  • Replies to a copied comment don’t trigger notifications to users mentioned or who created the original comment.
  • To associate copied comments with their new account, manually update comments with the new email address. 
Shared drives—A user's shared drive only migrates if it's mapped. Mapping a user, or the Drive service, doesn’t result in shared drive migration. When mapping shared drives, make sure a single shared drive is not mapped to multiple users. The target user is displayed as the creator of the drive if the drive doesn’t exist on the target account. Only managers of the shared drive are used to write files to it, so large shared drives with only a few managers might migrate slowly.
Migrating permissions to shared drives Restricted permissions (where a child file or folder has fewer permissions than its parent) are not supported by shared drives. If the file or folder has restricted permissions on the source environment, the restricted permissions are not migrated.

Internal content shared with users outside your organization—If users or groups outside your organization have a Google Account, you can add them to Drive files and folders and migrate those sharing permissions.

External users, or groups without a Google Account, can automatically receive an email with a custom access link at migration time.

You might want to reduce the amount of time that external users have access to your shared files and folders. If so, migrate this content during the final incremental migration and:

  • In your Google Admin console, turn on file sharing for people outside of your organization. For more details, go to Set Drive users' sharing permissions.
  • In the settings template, turn on Allow email invitations. External users are sent an email invitation with a link to the shared content once it's migrated. For more details, go to Understand settings templates.
Tip: Use the Permissions by Object report to identify externally shared objects before a migration. For more details, go to Understand scan reports.
Externally owned Drive files that have been shared with internal users

Files owned by users outside your organization can be migrated to the target account. Ownership is transferred to the first internal user to have the file migrated to them. Inform internal and external users about any potential change of ownership.

Tip: Use the Shared content by user report to identify externally owned files. For more details, go to Understand scan reports.

Links within migrated Drive files Link correction for both Google and non-Google files in Drive is not supported. Links must be corrected manually after a migration.
Google Forms response sheets
  • Responses aren’t migrated if the Sheet doesn’t have a linked response form.
  • If you have a response sheet that is linked to a Form, the association between the Form and Sheet is lost after a migration. The link can be restored manually.

For more details, go to Choose where to save form responses.

Running test migrations to Drive

If you delete items in the target Drive account following a test migration, make sure to empty the trash before rerunning the migration. Google Workspace Migrate tracks items by ID and resurrects items from the trash if you run a migration again. 

Emptying the trash avoids this issue and allows you to run a fresh migration.

Next step

Now it's time to set up a Google Workspace connection. To get started, go to Add a source connection.


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