Atlas supports deploying clusters onto Microsoft Azure. This page provides reference material related to Atlas cluster deployments on Azure.
Depending on your cluster tier, Atlas supports the following
Azure regions. While all of the following
M10+ clusters, some regions don't support Free or
Shared-Tier clusters. A check mark indicates support for Free clusters,
Shared-Tier clusters, or Availability Zones. The Atlas
Region is the corresponding region name used by Atlas processes.
Regions with Availability Zones guarantee higher uptime for dedicated clusters deployed after September 12, 2019. Existing clusters in regions with Availability Zones are not automatically migrated. To learn more about Availability Zones, see Azure's documentation.
Virginia (East US)
Sao Paulo, Brazil
Quebec City, QC, Canada
Toronto, ON, Canada
Due to their higher cost, it is recommended to use Switzerland West or UAE Central as a secondary disaster recovery (DR) region in a multi-region cluster if necessary.
- Use Switzerland West in conjunction with Switzerland North.
- Use UAE Central in conjunction with UAE North.
Cluster Configuration Options¶
Each Atlas cluster tier comes with a default set of resources. Atlas provides the following resource configuration options:
- Custom Storage Size
The size of the server root volume. Atlas clusters deployed onto Azure use premium storage disks. NoteRAM Availability
The actual amount of RAM available to each cluster tier might be slightly less than the stated amount, due to memory that the kernel reserves.
The following clusters tiers are available:Cluster TiersDefault StorageDefault RAMM22 GBSharedM55 GBSharedM1032 GB2 GBM2032 GB4 GBM3032 GB8 GBM40128 GB16 GBR40128 GB16 GBM50128 GB32 GBR50128 GB32 GBM60128 GB64 GBR60128 GB64 GBM80256 GB128 GBR80256 GB128 GBM200256 GB256 GBR200256 GB256 GBR300512 GB384 GBR400512 GB432 GB
Can use this tier for a multi-cloud cluster.
Not available in the following regions:
NoteCluster Tier & API Naming Conventions
For purposes of management with the Atlas API, cluster tier names that are prepended with
Rinstead of an
R40for example) run a low-CPU version of the cluster. When creating or modifying a cluster with the API, be sure to specify your desired cluster class by name with the
providerSettings.instanceSizeNameattribute.ImportantMulti-Cloud Low-CPU clusters
Low-CPU cluster tiers (R40, R50, R60, etc) are available in multi-cloud cluster configurations as long as the cluster tier is available for all the regions that the cluster uses.
Workloads typically require less than
Atlas configures the following resources automatically and does not allow user modification:
Azure Fault Domains¶
Each Azure region includes a set number of fault domains. Fault domains consist of a group of virtual machines that share a common power source and network switch. For regions that have at least three fault domains (3FD), Atlas deploys clusters across three fault domains. For regions that only have two fault domains (2FD), Atlas deploys clusters across two fault domains.
The Atlas Add New Cluster form marks regions that support 3FD clusters as Recommended, as they provide higher availability.
The number of fault domains in a region has no effect on the number of MongoDB nodes Atlas can deploy. MongoDB Atlas clusters are always made of replica sets with a minimum of three MongoDB nodes.
For general information on Azure regions and fault domains, see Manage the availability of Windows virtual machines in Azure
Regions with at Least Three Fault Domains¶
If the selected Azure region has at least three fault domains, Atlas clusters are split across three fault domains. For example, a three node replica set cluster would have one node deployed onto each zone.
3FD clusters have higher availability compared to 2FD clusters. However, not all regions support 3FD clusters.
Regions with Only Two Fault Domains¶
If the selected Azure region has two fault domains, Atlas clusters are split across the two fault domains. For example, a three node replica set cluster would have two nodes deployed to one zone and the remaining node deployed to the other zone.
2FD clusters have a higher chance of loss of availability in the event of the loss of an zone than 3FD clusters. However, where latency or location are a priority, a region that supports 2FD clusters may be preferred.
|||(1, 2) For detailed documentation on Azure storage options, see High-performance Premium Storage and managed disks for VMs|