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Elastic Compute Service

Scheduled maintenance window

Creating scheduled maintenance windows

If you create a maintenance window for a target instance, VolcanoEngine will automatically be authorized to redeploy your instance to a new host machine when a scheduled O&M event is triggered. This helps mitigate the risk of severe downtime caused by abnormally running hosts and ensures the continuity and stability of your business.

If the associated resources have already triggered a scheduled maintenance event in the Inquiring status when you create the scheduled maintenance window, you need to manually select a maintenance time and complete the authorization. Learn more.

warning

For instances mounted with local volumes: Redeploying instances will affect data stored on all local volumes (including both faulty and healthy volumes) associated with the instances. Please back up data in advance to prevent data loss. You can back up data using volumes, TOS, or other methods.

During the O&M period, operations such as shutdown and restart are performed on instances, which may impact your business. Please select an appropriate O&M time, such as during off-peak hours.

Prerequisites

To use tags to select target ECS instances for scheduled maintenance window operations, first associate the corresponding tags with the instances.

Limits

Associated object	Association relationship	Description
Scheduled maintenance window and resource object (instances selected by project)	One-to-one	Each scheduled maintenance window can be associated with only one resource object (project) and cannot be associated with multiple resource objects (projects) simultaneously. Each resource object (project) can be associated with only one scheduled maintenance window and cannot be associated with multiple scheduled maintenance windows.
Scheduled maintenance window and resource object (instances selected by tag)	One-to-ten	A single scheduled maintenance window can be associated with up to ten resource objects (tags). A single resource object (tag) can be associated with only one scheduled maintenance window.

Procedure

In the left-side navigation pane, select "Maintenance & Monitoring > System Events".

Select the region where your business is located.

Click the "Scheduled maintenance window" tab.

Click the "Create maintenance window" button and configure the parameters described in the following table.

Parameter	Description	Sample value
Window name	The name of the scheduled maintenance window.	Scheduled maintenance window for project A
Resource object	Target resource objects (instances) can be precisely selected by specifying a project or tag. tip After a scheduled maintenance window is configured to select resources by specifying a project or tag and is in the Enabled status, newly created instances that match the criteria will also be automatically included in the window's management scope. If configurations for both the "Specify project" and "Specify tag" parameters are present, the configuration selected at submission time takes precedence as the final effective rule. Specify project Resources covered by the scheduled maintenance window can be flexibly selected based on projects associated with instances. This is applicable to batch O&M scenarios. Specify tag Resources covered by the scheduled maintenance window can be flexibly selected based on custom tag key-value pairs (Key-Value) of instances. This is applicable to batch O&M scenarios.	Specify project/default
Window cycle	The preset time period for executing O&M operations. Supported options include "Daily" and "Weekly". tip We recommend configuring multiple time periods for a scheduled maintenance window to reduce the probability of mismatches between the actual required maintenance time and the scheduled window time, thereby improving the success rate of event execution. The window cycle uses UTC time by default, with Sunday 00:00 as the minimum starting point for configuration. The duration of a single time period within a single scheduled maintenance window must be at least 30 minutes. Daily Repeats the time window configuration on a daily basis, suitable for setting short, fixed maintenance periods each day with relatively minor impact and short duration. Click the "Add time range" button to set more maintenance time periods. Up to 10 time ranges can be added, and at least 1 time range is required. Weekly Repeats the time window configuration on a weekly basis, suitable for setting longer, fixed maintenance periods each week, which may have a greater impact and longer duration. Click the "Add time range" button to set more maintenance time periods. Up to 10 time ranges can be added, and at least 1 time range is required. tip The window cycle supports cross-week configuration, but the total duration cannot exceed one week (7 days).	Daily Start time: 00:00 End time: 02:00
Maintenance action	The default maintenance action of a scheduled maintenance window is "Redeploy", and cannot be modified.	Retain the default value
Enable maintenance window	Specifies whether to enable the scheduled maintenance window immediately upon creation. Enable (default): The scheduled maintenance window is enabled immediately upon creation. Disable: The scheduled maintenance window does not need to be enabled immediately upon creation. tip If you choose not to enable the window, you are required to manually enable it later for it to take effect.	Enable

Click the "Confirm" button to complete the operation.

Expected results

When a scheduled O&M event is triggered for resources associated with this maintenance window, VolcanoEngine is automatically authorized to deploy your instances to a new host. Upon successful authorization, the event status updates to Executing. And VolcanoEngine will perform the redeployment operation based on the configured window cycle. Once the deployment succeeds, the event status updates to Succeeded.

Last updated: 2026.02.05 14:45:08