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- Atlas M0 (Free Tier), M2, and M5 Limitations
Atlas M0 (Free Tier), M2, and M5 Limitations¶
Configuration 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 |
|
| MongoDB Version and Storage Engine | Atlas uses MongoDB 4.2 for MongoDB 4.4 on Shared Tier Clusters You can deploy MongoDB 4.4 in Atlas free and shared-tier
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 Tier
cluster. |
| Cluster Memory | You cannot configure memory for M0 Free Tier or M2/M5
shared clusters. |
| Cluster Storage | You cannot configure storage size for M0 Free Tier or
M2/M5 shared clusters. |
| Replication Factor | Replication Factor is set to 3 Nodes and cannot be modified
for M0 Free Tier, or M2/M5 shared clusters. |
| Replica Set Tags | M0 Free Tier, 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 Tier or M2/M5 shared
cluster as a Sharded Cluster. |
| Do You Want To Enable Backup | You cannot enable backups on Backup Alternative: mongodump 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 Tier
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 Tier or M2/M5 shared clusters. |
| Network Peering Connections | You cannot configure Set up a Network Peering Connection on
M0 Free Tier or M2/M5 shared clusters. |
| Access Tracking | You cannot view the database access history for M0 Free
Tier, or M2/M5 shared clusters. |
Operational Limitations¶
The following table lists the operational limitations of Atlas
M0 Free Tier and M2/M5 shared clusters:
| Configuration Option | Limitation |
|---|---|
| Aggregation | Atlas On Free Tier 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 Tier and shared clusters, aggregation pipelines are restricted to 50 stages. |
| Throughput | Maximum operations:
|
| Sort in Memory | M0/M2/M5 sort in memory limit is 32 MB. |
| Query Utilization | The percentage of time that a query is running over any five
minute period must remain under 100% on M0 Free Tier and
M2/M5 shared clusters. |
| Connections | M0 Free Tier and M2/M5 shared clusters are allowed a
maximum of 500 connections. |
| Data Transfer Limits |
Atlas throttles the network speed of clusters which exceed the posted limits. |
| JavaScript |
Example $where and map-reduce are not supported. |
| API Access | You cannot modify or configure an M0 Free Tier cluster
using the Clusters API endpoint. A
subset of API endpoints support M2 and M5 shared
clusters. |
| Number of Free Tier clusters | You can deploy at most one M0 Free Tier cluster per
Atlas project. |
| 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. |
| Atlas Monitoring | The Metrics view of an
For more information on these metrics, see Real Time Metrics. |
| Atlas Alerts |
|
| Namespaces and Database Names | M0 Free Tier and M2/M5 shared cluster namespaces are
limited to 95 bytes. Database names are limited to 38 bytes. |
| Database and Collections | M0 Free Tier and M2/M5 shared clusters have a maximum
of 100 databases and 500 collections total. |
| Database Logs | M0 Free Tier and M2/M5 shared clusters do not provide
downloadable logs. |
| Cluster Persistence | Atlas may deactivate idle M0 Free Tier clusters as per
the Terms of Service. |
| Auto-Expand Storage | M0 Free Tier and M2/M5 shared clusters do not provide
automatically scaling storage. |
| Performance Advisor | M0 Free Tier and M2/M5 shared clusters do not provide
access to the Performance Advisor. |
| Real-Time Performance Panel | M0 Free Tier and M2/M5 shared clusters do not provide
access to the Real-Time Performance Panel. |
| Build Index with Rolling Build | M0 Free Tier and M2/M5 shared clusters do not provide
the ability to build indexes with a rolling build. |
| Custom Roles | Changes to custom roles
make take up to 30 seconds to deploy in M0 Free Tier and
M2/M5 shared clusters. |
| Cursors | Free tier and shared clusters cannot use the noTimeout cursor option. |
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: |