The ConfigServer component stores metadata for your sharded cluster, including the cluster's configuration and how data is distributed across shards. When a ConfigServer runs low on storage or hits a performance limit, scale out its storage space or change its specifications.
Prerequisites
Before you begin, ensure that:
The instance uses enterprise SSDs (ESSDs).
Billing
For pricing details, see Configuration change fees.
Usage notes
The storage space you select must be greater than or equal to the storage space already used by the ConfigServer. To reduce storage space, create a new instance and migrate your data. For details, see Other configuration change scenarios and methods.
During a configuration change, the instance may experience one or two transient connections, each lasting about 30 seconds. Schedule changes during off-peak hours to minimize impact.
Configure your application to automatically reconnect to the instance.
If your database's minor version is expired or no longer maintained, the system upgrades it to the latest minor version during the change.
When changing storage space only, the behavior depends on available host resources:
Sufficient resources: Storage scales out on the local host. No migration or switchover occurs, no transient connections happen, and the change takes effect immediately.
Insufficient resources: A cross-host migration and switchover are required. Transient connections occur during the process, and the change takes effect at the switchover time you specify.
Change the ConfigServer configuration
Go to the MongoDB sharded cluster instances page. In the top navigation bar, select a resource group and region, then click the ID of the target instance.
On the Basic Information page, find the Configserver List section and locate the target ConfigServer. In the Actions column, click
and select the appropriate option:Subscription instance: Select Upgrade or Downgrade.
Pay-as-you-go instance: Select Change Configurations.
Configure the following parameters.
Parameter Description Category Select a new category for the ConfigServer. This parameter applies only to instances that use cloud disks. If a category is unavailable, it is not supported in the current zone. For supported categories and specifications, see Sharded cluster instance specifications. Instanses Select new specifications and storage space. The storage space must be greater than or equal to the current ConfigServer's maximum storage space. Switchover time Select when the change takes effect: Switch Immediately After Task Completion applies the change as soon as the task finishes. Switch Within Maintenance Window After Task Completion delays the change to a maintenance window. To update the maintenance window, see Set a maintenance window. Complete the purchase based on your billing method:
Pay-as-you-go: Click Pay Now. The fee is deducted automatically within the next hour.
Subscription: Click Pay Now and complete the payment on the Payment page.
During the configuration change, the instance status shows Modifying. When the status changes to Running, the change is complete.
API reference
| API | Description |
|---|---|
| ModifyNodeSpec | Changes the specifications and storage space of a single Mongos, shard, or ConfigServer node in a sharded cluster instance. |