Create a Cluster

Considerations

• Clusters can span regions and cloud service providers. The total number of nodes in clusters spanning across regions has a specific constraint on a per-project basis.

  Atlas limits the total number of nodes in other regions in one project to a total of 40. This total excludes:

  • Google Cloud regions communicating with each other

  • Free clusters or shared clusters

  The total number of nodes between any two regions must meet this constraint.

  Example

  If an Atlas project has nodes in clusters spread across three regions:

  • 30 nodes in Region A

  • 10 nodes in Region B

  • 5 nodes in Region C

  You can only add 5 more nodes to Region C because:

  1. If you exclude Region C, Region A + Region B = 40.

  2. If you exclude Region B, Region A + Region C = 35, <= 40.

  3. If you exclude Region A, Region B + Region C = 15, <= 40.

  4. Each combination of regions with the added 5 nodes still meets the per-project constraint:

     • Region A + B = 40

     • Region A + C = 40

     • Region B + C = 20

  You can't create a multi-region cluster in a project if it has one or more clusters spanning 40 or more nodes in other regions.

  Contact Atlas support for questions or assistance with raising this limit.

• Each Atlas project supports up to 25 database deployments. Please contact Atlas support for questions or assistance regarding the database deployment limit. To contact support, select Support from the left-hand navigation bar of the Atlas UI.

• If your Atlas project contains a custom role that uses actions introduced in a specific MongoDB version, you must delete that role before creating clusters with an earlier MongoDB version.

• Atlas clusters created after July 2020 use TLS version 1.2 by default.

• When you create a cluster, Atlas creates a network container in the project for the cloud provider to which you deploy the cluster if one does not already exist.

Procedure