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Configure and Enable Atlas Device Sync
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You can configure and enable Atlas Device Sync via the App Services UI, Realm CLI, or the Atlas App Services Admin API. You can update an existing configuration in the same way. If it is your first time enabling Device Sync, the UI is a great choice because it walks you through the required steps.
You might want to alter your Atlas Device Sync configuration after you have already enabled Device Sync. You can update a configuration using the same procedure as enabling Device Sync in the first place. If you're using Flexible Sync mode, you can update your configuration without needing to terminate and re-enable Sync.
If you're re-enabling Device Sync after pausing or terminating it, refer to Resume or Re-Enable Device Sync.
If you are using the older Partition-Based Sync mode, refer to Alter Your Partition-Based Sync Configuration.
Device Sync pauses automatically after 30 days of inactivity.
If you haven't already decided how you want to configure your data model, see Sync Data Model Overview.
Unless you are using Development Mode, you must
specify at least one valid schema for a collection in the
synced cluster before enabling Sync. At a minimum, the schema must define
_id as a primary key. You should also include the field(s) you intend to use
as your queryable fields.
For more details on how to define a schema, see Enforce a Schema.
Flexible Sync Prerequisites
Enabling Flexible Sync in Your App Services Application requires a non-sharded MongoDB Atlas cluster running MongoDB 5.0 or greater