Create a Cluster

Required Access

To create a cluster, you must have Organization Owner, Project Owner, or Project Cluster Creator access to the project.

Considerations

• To minimize network latency and data transfer costs, and to increase overall stability and security, use the same cloud provider and region to host your application and cluster when possible.

• 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, not including:

  • Google Cloud regions communicating with each other

  • Free clusters

  • Flex clusters

  Sharded clusters include additional nodes. The electable nodes on the dedicated Config Server Replica Set (CSRS) count towards the total number of allowable nodes. Each sharded cluster has an additional electable node per region as part of the dedicated CSRS. To learn more, see Replica Set Config Servers.

  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.

• M30 and higher clusters are recommended for production environments. Clusters with sustained loads on M10 and M20 tiers may experience degraded performance over time.

• Each Atlas project supports up to 25 clusters. If you have questions or need assistance regarding the cluster limit, contact support.

• 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.

  Important

  Beginning July 31st, 2025, Atlas will no longer support TLS 1.0 or 1.1 under any circumstance. Atlas will upgrade all clusters to reject attempts to connect with TLS 1.0 or 1.1.

  Any client connections configured for TLS 1.0 or 1.1 will undergo a service outage during this upgrade. To avoid this, set the minimum TLS version of your clusters to 1.2 at your earliest opportunity.

• 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.

• If you have a Backup Compliance Policy enabled, all new and existing clusters have Cloud Backup automatically enabled and use the project-level Backup Compliance Policy. Atlas augments any preexisting cluster-level policies to meet the minimum requirements of the Backup Compliance Policy. All new clusters use the Backup Compliance Policy unless the mininum requirements of the cluster-level backup policy expand beyond the mininum requirements of the Backup Compliance Policy.

Procedure