Atlas M0 (Free Cluster), M2, and M5 Limitations¶
Configuration Limitations¶
The following table lists the configuration limitations of Atlas
M0 free clusters and M2/M5 shared clusters:
Configuration Option | Limitation |
|---|---|
Cloud Service Provider and Region |
|
MongoDB Version and Storage Engine | Atlas uses MongoDB 4.4 for M0/M2/M5 clusters. |
MongoDB Version Upgrade | You can't upgrade the MongoDB version that Atlas upgrades |
Cluster Tier | You must select the M0 cluster tier to deploy a free cluster. |
Cluster Memory | You cannot configure memory for M0 free clusters or M2/M5
shared clusters. |
Cluster Storage | You cannot configure storage size for M0 free clusters or
M2/M5 shared clusters. |
Replication Factor | Replication Factor is set to 3 Nodes and cannot be modified
for M0 free clusters or M2/M5 shared clusters. |
Replica Set Tags | M0 free clusters and M2/M5 shared clusters are not
configured with pre-defined
replica set tags. |
Do You Want A Sharded Cluster | You cannot deploy a M0 free cluster or M2/M5 shared
cluster as a Sharded Cluster. |
Do You Want To Enable Backup | You cannot enable backups on Tip See also: Backup Alternative: You may use mongodump to back up your data and mongorestore to restore that data. To learn how to manually back up your data, see Command Line Tools. |
Test Failovers | You cannot perform primary failover testing on M0 free clusters
or M2/M5 shared clusters. |
Database Auditing | You cannot configure
database auditing on M0 Free
Tier or M2/M5 shared clusters. |
Encryption at Rest using your Key Management | You cannot configure Encryption at Rest using Customer Key Management on
M0 free clusters or M2/M5 shared clusters. |
Network Peering Connections | You cannot configure Set up a Network Peering Connection on
M0 free clusters or M2/M5 shared clusters. |
Access Tracking | You cannot view the database access history for M0 Free
Tier, or M2/M5 shared clusters. |
Configure TLS Certificate Root | You cannot modify the Certificate Authority that MongoDB Atlas clusters
use through the API for M0 free clusters and M2/M5 shared clusters. |
Operational Limitations¶
The following table lists the operational limitations of Atlas
M0 free clusters and M2/M5 shared clusters:
Operation | Limitation |
|---|---|
Atlas free clusters and shared clusters do not support the
On free clusters and shared clusters, aggregation fields that represent database and collection names (such as $merge into and $out values) cannot accept expressions as values. On free clusters and shared clusters, aggregation pipelines are restricted to 50 stages. | |
API Access | You cannot modify or configure an M0 free cluster
using the Clusters API endpoint. A
subset of API endpoints support M2 and M5 shared clusters. |
Atlas Alerts |
|
Atlas Monitoring | The Metrics view of an
For more information on these metrics, see Real Time Metrics. |
Authentication |
|
Auto-Expand Storage | M0 free clusters and M2/M5 shared clusters do not provide
automatically scaling storage. |
BSON Nested Object Depth | M0 free clusters and M2/M5 shared clusters
can't store documents with more than 50 nested levels. |
Build Index with Rolling Build | M0 free clusters and M2/M5 shared clusters do not provide
the ability to build indexes with a rolling build. |
Cluster Persistence | Atlas may deactivate idle M0 free clusters as per
the Terms of Service. |
Connections | M0 free clusters and M2/M5 shared clusters are allowed a
maximum of 500 connections. |
Cursors | Free clusters and shared clusters cannot use the noTimeout
cursor option. |
Custom Roles | Changes to custom roles
make take up to 30 seconds to deploy in M0 free clusters and
M2/M5 shared clusters. |
Database and Collections | M0 free clusters and M2/M5 shared clusters have a maximum
of 100 databases and 500 collections total. |
Database Commands | Certain database commands are unsupported or behave
differently in an Please contact Atlas support for any questions or comments related to restricted commands. |
Database Logs | M0 free clusters and M2/M5 shared clusters do not provide
downloadable logs. |
Data Recovery |
|
Data Transfer Limits |
Atlas throttles the network speed of clusters which exceed the posted limits. |
JavaScript |
Example $where and map-reduce are not supported. |
Namespaces and Database Names | M0 free cluster and M2/M5 shared cluster namespaces are
limited to 95 bytes. Database names are limited to 38 bytes. |
Number of Free Clusters | You can deploy at most one M0 free cluster per
Atlas project. |
Performance Advisor | M0 free clusters and M2/M5 shared clusters do not provide
access to the Performance Advisor. |
Query Utilization | The percentage of time that a query is running over any five
minute period must remain under 100% on M0 free clusters and
M2/M5 shared clusters. |
Real-Time Performance Panel | M0 free clusters and M2/M5 shared clusters do not provide
access to the Real-Time Performance Panel. |
Sort in Memory | M0/M2/M5 sort in memory limit is 32 MB. |
Throughput | Maximum operations:
|
Automatic Pause of Idle Clusters | Atlas automatically pauses M0 clusters after 60 days of
inactivity where there are zero connections to the cluster. You
can resume the cluster at any time. |
Driver Minimum Requirements¶
Driver | Description | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Drivers that use a JRE or JDK' | Due to an issue with TLS 1.3 support in the Java JDK' (JDK-8236039), upgrade the JDK' that supports the driver you use to connect to Atlas. Minimum versions of the JDK' include:
To check if other Java-based languages, libraries, and drivers support the change to TLS 1.3, refer to their documentation: |