MongoDB Atlas

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MongoDB Atlas is a cloud service for running, monitoring, and maintaining MongoDB deployments, including the provisioning of dedicated servers for the MongoDB instances.

MongoDB Deployments

MongoDB deployments, or “clusters” in Atlas, can be either a replica set or a sharded cluster.

Atlas uses MongoDB 3.2 with the WiredTiger storage engine. As new 3.2 maintenance releases become available, Atlas will automatically upgrade to these releases via a rolling process to maintain cluster availability.

Atlas deploys each cluster across a minimum of three availability zones and with mandatory security.

Each mongod process is deployed to its own AWS EC2 instance. For sharded clusters, the six routers (the mongos processes) run on six of the shard servers; i.e. each of the six mongos processes shares an AWS EC2 instance with one mongod process.

If the workload on the Atlas cluster is such that it impedes operations, including the ability to scale, MongoDB Atlas will create indexes in your cluster.

Atlas Group

Your Atlas group manages your MongoDB deployments. An Atlas group can have multiple MongoDB clusters.

A unique AWS Virtual Private Cloud (VPC) is created for each Atlas group. All clusters for the group are deployed inside this VPC. This region-specific VPC is created for the Atlas group during the deployment of the group’s first cluster.


Atlas secures your deployments through the use of TLS/SSL, virtual private cloud (VPC) subnet with IP whitelists, and user authentication and authorization.


Atlas provides support for the use of the service itself. Support for development and performance of the database itself requires a MongoDB subscription. For details, contact MongoDB Inc..