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Atlas M0 (Free Tier), M2, and M5 Limitations

The following table lists the configuration limitations of Atlas M0 Free Tier and M2/M5 shared clusters:

Configuration Option Limitation
Cloud Service Provider and Region

Atlas can deploy M0 Free Tier clusters to the Amazon Web Services us-east-1 (N. Virginia, USA) or eu-central-1 (Frankfurt, Germany) region. This does not affect other clusters in the Atlas project.

Atlas can deploy M2 and M5 clusters to a subset of regions on Amazon Web Services, Google Cloud Platform, and Microsoft Azure.

MongoDB Version Version is set to MongoDB 3.4 with Wired Tiger and cannot be modified.
Instance Size You must select the M0 instance size to deploy a Free Tier cluster.
Instance Memory You cannot configure memory for M0, M2, or M5 instances.
Instance Storage You cannot configure storage size for M0, M2 and M5 instances.
Replication Factor Replication Factor is set to 3 Nodes and cannot be modified.
Do You Want A Sharded Cluster You cannot deploy a M0 Free Tier or M2/M5 shared cluster as a Sharded Cluster.
Do You Want To Enable Backup You cannot enable backups.
Test Failovers You cannot perform primary failover testing.

The following table lists the operational limitations of Atlas M0 Free Tier and M2/M5 shared clusters:

Aggregation Atlas Free Tier clusters do not support the allowDiskUse option for the aggregation command or its helper method.
Throughput Maximum of 100 operations per second.
Query Utilization The percentage of time that a query is running over any five minute period must remain under 100%.
Connections Maximum of 100 connections.
Network bandwidth Restricted to 1GB per week in and 1GB per week out. Atlas throttles traffic to 1KB/s after reaching either bandwidth limit.
Javascript M0 Free Tier and M2/M5 shared clusters do not support server side javascript. For example, $where and map-reduce are not supported.
Data Explorer Data Explorer is not available for a Free Tier cluster.
API Access You cannot modify or configure an M0 Free Tier cluster using the Clusters API endpoint. A subset of API endpoint’s support M2 and M5 clusters.
Number of Free Tier clusters You can deploy at most one Free Tier cluster per Atlas project.
Database Commands

Certain database commands are unsupported or behavior differently in a Free Tier cluster. See Command Limitations in Free Tier Clusters for more information.

Please contact Atlas support for any questions or comments related to restricted commands.

Atlas Monitoring

The Metrics view of an M0 Free Tier or M2/M5 shared cluster only displays the following metrics:

  • Connections
  • Logical Size
  • Network
  • Opscounter

For more information on these metrics, see Real Time Metrics.

Namespaces and Database Names Namespaces are limited to 95 bytes. Database names are limited to 38 bytes.
Database and Collections Maximum of 100 databases and 500 collections total.
Cluster Persistance Atlas may terminate idle Free Tier clusters as per the Terms of Service.
VPC Peering M0 Free Tier and M2/M5 shared clusters do not support VPC peering.
Database Logs M0 Free Tier and M2/M5 shared clusters do not provide downloadable logs.
Auto-Expand Storage M0, M2, and M5 clusters do not provide automatically scaling storage.