You can change the configuration of a standalone or replica set instance if the configuration is excessive or cannot meet the performance requirements of your application.

Precautions

  • When you change the configuration, the new storage space must be larger than the storage space occupied by the current instance.
  • If the billing method is subscription, the interval between two configuration downgrades cannot be less than 60 days.
  • When the billing method is subscription, you cannot downgrade the storage space. You can use other methods to reduce the storage space. For more information, see Configuration change overview.
  • You cannot change the instance type (such as from a standalone instance to a replica set instance) or the storage engine. You can use other methods to change these items. For more information, see Configuration change overview.

Billing rules

For more information, see Configuration change fees.

Impacts

  • Changing configurations does not cause data loss.
  • Pre-operations for configuration changes to an instance do not affect the running of the instance. However, when configuration changes are formally executed on the instance, most operations related to databases, accounts, and network cannot be performed. One or two transient disconnections of up to 30 seconds will occur. For more information, see Select switching time.
  • The duration of a configuration change depends on various factors such as network conditions, task queues, and data volume. We recommend that you change configurations during off-peak hours and make sure that your applications have automatic reconnection mechanisms.

Select switching time

On the Change Configuration, you can specify switching time. The following table describes details about switching time.

Item Instance status Impact
Switch Within Maintenance Window The instance immediately enters the Changing Configuration state.

The system performs pre-operations, which do not affect the running of the instance or cause transient disconnections. Configuration changes are formally executed within the maintenance period you set.

For example, if the preset maintenance period is 2:00 to 3:00, configuration changes will be performed during this period. Most operations related to databases, accounts, and network cannot be performed. One or two transient disconnections of up to 30 seconds will occur.

Note For more information about how to modify a maintenance period, see Specify a maintenance period.
Switch Immediately After Data Migration

Configuration changes are performed immediately. Most operations related to databases, accounts, and network cannot be performed. One or two transient disconnections of up to 30 seconds will occur.

Procedure

  1. Log on to the ApsaraDB for MongoDB console.
  2. In the upper-left corner of the page, select the region of the instance.
  3. In the left-side navigation pane, click Replica Set Instances.
  4. Change the configuration of the instance.
    If the billing method of the instance is pay-as-you-go, perform the following steps:
    1. Find the instance and click its ID.
    2. In the Basic Information section, click Change Configuration.
      Change Configuration
    If the billing method of the instance is subscription, perform the following steps:
    1. Find the instance and click its ID.
    2. In the Basic Information section, click Upgrade or Downgrade.
      Upgrade or Downgrade
  5. On the Change Configuration page, specify Replication Factor, Specifications, Storage, and Migration Time of the instance.

    For more information about instance specifications, see Instance types.

    Note
    • For more information about the limits on parameters, see Precautions.
    • For more information about the selection and impacts of Migration Time, see Select switching time.
  6. Select ApsaraDB for MongoDB Terms of Service and make the payment as prompted.

Result

When the instance status changes to Running, the configuration has been changed.