For scheduled O&M events, you can be notified by text messages, phone calls, emails, or internal messages. You can also be notified in the console. Scheduled PolarDB O&M events include database software upgrade events and hardware maintenance and upgrade events. You can view the details of each scheduled event. These details include the event type, task ID, cluster name, and switch time. You can also change the switch time.

Note

  • If you have pending O&M events and want to view event notifications, you can go to the left-side navigation pane in the console and choose Event Center > Scheduled Events. Pending events
  • In most cases, you are notified of scheduled events in ApsaraDB at least three days before these events are executed. You can be notified in many ways. For example, you can be notified by , phone calls, emails, or internal messages. You can also be notified in the console. You must log on to Message Center, enable ApsaraDB Fault or Maintenance Notifications, and specify a contact. We recommend that you specify an O&M engineer as the contact.
    Figure 1. Message Center settings
    Message Center settings

Procedure

  1. Log on to the PolarDB console.
  2. In the upper-left corner of the console, select the region where the cluster that you want to manage is deployed.
  3. In the left-side navigation pane, choose Event Center > Scheduled Events.
    Note For an O&M event for which you must reserve the switch time, a message box appears to prompt you to complete the reservation in time.
  4. On the Scheduled Events page, you can view the details of the event. To change the switch time of the event, select the cluster that you want to manage and click Add Scheduled Event.
  5. In the Add Scheduled Time dialog box, configure Scheduled Switching Time and click OK.
    Note
    • You can select Set the earliest execution time. If you select this item, the system automatically enters the earliest scheduled switch date and time. After you click OK, the events in the cluster are pending for processing. If you clear Set the earliest execution time, you can change the scheduled switch date and time.
    • The time that is specified by the value of Scheduled Switching Time cannot be later than the time that is displayed in the Start Deadline column.

Causes and impacts of events

Cause Impact Impact description
Instance migration Transient connection
In most cases, Scheduled failover time This may have the following impacts on your instance:
  • Your instances or data shards in your instances experience transient connections and stay in the read-only state for up to 30 seconds before all the data is synchronized. We recommend that you perform the failover during off-peak hours. Make sure that your application can be automatically reconnected to your database system.
  • You cannot manage your instances by using Data Management (DMS) or Data Transmission Service (DTS). This impact is temporary.
Failover between primary and read-only nodes
Instance parameter adjustment
Host vulnerability fixing
SSL certificate update
Backup mode change
Minor version upgrade Transient connection
In most cases, Scheduled failover time This may have the following impacts on your instance:
  • Your instances or data shards in your instances experience transient connections and stay in the read-only state for up to 30 seconds before all the data is synchronized. We recommend that you perform the failover during off-peak hours. Make sure that your application can be automatically reconnected to your database system.
  • You cannot manage your instances by using Data Management (DMS) or Data Transmission Service (DTS). This impact is temporary.
Differences between minor versions

Different minor versions provide different features. Minor versions are kernel versions. Before you upgrade the minor version of the instance, you must take note of the differences between the previous and new minor versions. For more information, see Release notes for the minor version of the ApsaraDB PolarDB MySQL-compatible edition.

Proxy minor version upgrade Transient connection
In most cases, Scheduled failover time This may have the following impacts on your instance:
  • Your instances or data shards in your instances experience transient connections and stay in the read-only state for up to 30 seconds before all the data is synchronized. We recommend that you perform the failover during off-peak hours. Make sure that your application can be automatically reconnected to your database system.
  • You cannot manage your instances by using Data Management (DMS) or Data Transmission Service (DTS). This impact is temporary.
Differences between minor versions Different minor versions provide different features. Before you upgrade the minor version of the instance, you must take note of the differences between the previous and new minor versions.
Network upgrade Transient connection
In most cases, Scheduled failover time This may have the following impacts on your instance:
  • Your instances or data shards in your instances experience transient connections and stay in the read-only state for up to 30 seconds before all the data is synchronized. We recommend that you perform the failover during off-peak hours. Make sure that your application can be automatically reconnected to your database system.
  • You cannot manage your instances by using Data Management (DMS) or Data Transmission Service (DTS). This impact is temporary.
VIP connections In some network upgrades, data may be migrated across zones. In this case, the virtual IP address (VIP) of the instance changes. If a database client uses a VIP to connect to the instance, the connection is interrupted.
Note We recommend that you use a domain name to connect to the instance and disable the DNS cache of your application and the DNS cache of the server on which your application runs.
Storage gateway upgrade I/O jitter Temporary I/O jitter may occur or the SQL latency may increase. This impact lasts no more than 3 seconds.

Related operations

Operation Description
DescribePendingMaintenanceActions Queries the numbers of pending events for different types of tasks.
ModifyPendingMaintenanceAction Modifies the task switch time of pending events.
DescribePendingMaintenanceAction Queries the details about pending events.