You can receive notifications for ApsaraDB for Redis events such as instance migrations and version upgrades by email, internal message, or by using the ApsaraDB for Redis console. For pending events, you can view event types, regions, procedures, considerations, affected instances, and the default switchover time. You can also adjust the scheduled switchover time.

Precautions

  • In the upper part of the Instances page in the ApsaraDB for Redis console, you can view the number of pending events. A value of 0 indicates no pending events.
  • In most cases, notifications for system maintenance events such as instance migrations and version upgrades are sent at least three days before execution. Notifications for high-risk vulnerability fixes are sent three or fewer days before execution due to the urgency of these events.

    You can receive notifications by email, internal message, or by using the ApsaraDB for Redis console. To use this feature, log on to the Message Center, select ApsaraDB Fault or Maintenance Notifications, and then specify a contact. We recommend that you specify an O&M engineer as the contact.

    Note To be notified of pending event updates such as new pending events and task progress at the earliest opportunity, you can configure alert rules for pending events in the CloudMonitor console. For more information, see Subscribe to event notifications.
    Figure 1. Message Center settings
    Message Center settings

Procedure

  1. Log on to the ApsaraDB for Redis console.
  2. In the left-side navigation pane, choose Event Center > Scheduled Event.
    Note You can also click Pending Events in the upper part of the Instances page.
  3. On the Scheduled Event page, view the event details.
    The details about an event include Instance ID, Event Type, Cause, Business Impact, and Scheduled Disconnection Time. For more information about the causes and impacts on business, see Causes and impacts of events.
    The system automatically performs a switchover on the related instance at the specified Scheduled Disconnection Time. If the scheduled switchover time is not during off-peak hours, perform the following steps to modify the Scheduled Disconnection Time.
  4. Optional: Modify the Scheduled Disconnection Time.
    You can use the default switchover time, modify the scheduled switchover time, or configure the periodic switchover time. The system performs the switchover based on the following priority: scheduled switchover time > periodic switchover time > default switchover time.
    Type and description of the switchover time Procedure
    Scheduled switchover time

    You can adjust the scheduled switchover time of an event based on actual needs.

    1. On the Scheduled Event page, select one or more events.
    2. In the upper-left corner of the Scheduled Event page, click Add Scheduled Event.
    3. In the Add Scheduled Event panel, set the scheduled switchover time.

      If you need to immediately perform the switchover, select Earliest Execution Time. After you confirm the settings, the system starts the preparation and immediately performs a switchover after the preparation is complete.

      Note The time specified by Scheduled Disconnection Time cannot be later than the time specified by Set Before.
    4. Check whether the correct events are selected.
      • If yes, click Save to save the settings.
      • If no, select the correct events on the Scheduled Event page and set the scheduled switchover time again.
    Periodic switchover time

    After you specify the periodic switchover time, the system performs switchovers for pending events that have not been executed at the scheduled switchover time and events that have no scheduled switchover time specified at the periodic switchover time.

    For example, if you set the periodic switchover time to 00:00 on Tuesday, the system performs switchovers on multiple instances related to the pending events at the same time. This reduces the impacts caused by the switchovers.

    1. In the upper-left corner of the Scheduled Event page, click Global Scheduler.
    2. In the Global Scheduler panel, specify the periodic switchover time in the Week or Month dimension based on your business requirements.
      Note You can view the specified periodic switchover time in the upper-right corner of the Scheduled Event page. If you select None, the periodic switchover time is not displayed.
    3. Click Save to save the settings.
  5. Optional: Cancel the scheduled switchover for an event.
    You can cancel the scheduled switchover for a Minor Version Update event. You can select the Minor Version Update event and click Cancel Scheduled Event in the upper-left corner.

Causes and impacts of events

Cause Impact Description
Instance migration Transient connections
When the switchover is performed at the scheduled switchover time you may experience the following impacts. We recommend that you perform the switchover during off-peak hours and make sure that your applications are configured to automatically re-establish a connection.
  • Single-zone instance: One switchover is performed. Your instance or data shards in your instance that are involved in the switchover experience transient connections and stay in the read-only state for up to 30 seconds until all the data is synchronized.
  • Multi-zone instance: Two switchovers are performed. During the switchovers, your instance or data shards in your instance that are involved in the switchovers experience transient connections and stay in the read-only state for up to 30 seconds until all the data is synchronized. The second switchover switches the master node to the primary zone. This prevents an increase in access latency that may occur when the master node is in the secondary zone.
Note During the switchover, you cannot manage your instance by using Data Management (DMS) or Data Transmission Service (DTS). This impact is temporary.
Switchover between master and replica nodes
Zone migration
Minor version update Transient connections
When the switchover is performed at the scheduled switchover time you may experience the following impacts. We recommend that you perform the switchover during off-peak hours and make sure that your applications are configured to automatically re-establish a connection.
  • Single-zone instance: One switchover is performed. Your instance or data shards in your instance that are involved in the switchover experience transient connections and stay in the read-only state for up to 30 seconds until all the data is synchronized.
  • Multi-zone instance: Two switchovers are performed. During the switchovers, your instance or data shards in your instance that are involved in the switchovers experience transient connections and stay in the read-only state for up to 30 seconds until all the data is synchronized. The second switchover switches the master node to the primary zone. This prevents an increase in access latency that may occur when the master node is in the secondary zone.
Note During the switchover, you cannot manage your instance by using Data Management (DMS) or Data Transmission Service (DTS). This impact is temporary.
Differences between minor versions Different minor versions (kernel versions) have different updates. You must take note of the differences between the current minor version and the minor version to which your instance is updated.
Minor version update for proxy nodes Transient connections
When the switchover is performed at the scheduled switchover time you may experience the following impacts. We recommend that you perform the switchover during off-peak hours and make sure that your applications are configured to automatically re-establish a connection.
  • Single-zone instance: One switchover is performed. Your instance or data shards in your instance that are involved in the switchover experience transient connections and stay in the read-only state for up to 30 seconds until all the data is synchronized.
  • Multi-zone instance: Two switchovers are performed. During the switchovers, your instance or data shards in your instance that are involved in the switchovers experience transient connections and stay in the read-only state for up to 30 seconds until all the data is synchronized. The second switchover switches the master node to the primary zone. This prevents an increase in access latency that may occur when the master node is in the secondary zone.
Note During the switchover, you cannot manage your instance by using Data Management (DMS) or Data Transmission Service (DTS). This impact is temporary.
Differences between minor versions Different minor versions have different updates. You must take note of the differences between the current minor version and the minor version to which your proxy nodes are updated.

FAQ

For more information, see FAQ about pending events.

Related API operations

Operation Description
ModifyActiveOperationTask Modifies the scheduled switchover time for an O&M task of an ApsaraDB for Redis instance.