Global Clusters

The Global Clusters endpoints provide the ability to add, remove, and retrieve managed namespaces and custom zone mappings associated with Global Clusters. Each collection in a Global Cluster is associated with a managed namespace. For example, the namespace for the publishers collection in the partners database is partners.publishers.

When you create a managed namespace for a Global Cluster, Atlas creates an empty collection for that namespace. In addition, Atlas recreates the collection associated with a managed namespace if you delete the collection using mongosh. However, the recreated collection is empty; Atlas does not repopulate it with data.

Atlas shards the empty collection using the required location field and a custom shard key. For example, if the your custom shard key is city, the compound shard key is location, city.

Each Global Cluster is also associated with one or more Global Writes Zones. When a user creates a Global Cluster, Atlas automatically maps each location code to the closest geographical zone. Custom zone mappings allow administrators to override these automatic mappings. For example, a use case may require mapping a location code to a geographically distant zone. Administrators can manage custom zone mappings with the APIs below and the Global Cluster Configuration pane when you create or modify your Global Cluster.