Schedules simulated system events for one or more Elastic Compute Service (ECS) instances. The system events that are simulated do not occur in the real system and the simulation does not affect ECS instances.


  • You can view the scheduled system events in the ECS console, ECS API, or cloud monitoring service.

  • The following table describes the life cycle of a simulated system event.

    Name Description Status
    Scheduled The simulated system event has been scheduled. The status for the simulated system event is automatically changed to Scheduled after the schedule.
    Executed The simulated system event has been executed. The status for the simulated system event is automatically changed to Executed at the scheduled time specified by the NotBefore parameter if no manual intervention is involved.
    Canceled The simulated system event has been canceled. The status for the simulated system event is changed to Canceled if you cancel the event by making a CancelSimulatedSystemEvents request.
    Avoided The simulated system event has been avoided. The status for the simulated system event of maintenance-triggered instance restart can be changed to Avoided if you restart the instance before the scheduled time of the simulated system event. The maintenance-triggered instance restart is indicated by the SystemMaintenance.Reboot value.

Request parameters

Name Type Required Description
Action String Yes The operation that you want to perform. Value: CreateSimulatedSystemEvents.
RegionId String Yes The ID of the region.For more information, call DescribeRegions to obtain the latest region list.
InstanceId.N String Yes The IDs of one or more ECS instances. Value range of N: [1, 100]. The ECS IDs must be displayed in a repeated list format.
EventType String Yes The type of a system event. Optional values:
  • SystemMaintenance.Reboot: The instance restarts because of maintenance.
  • SystemFailure.Reboot: The instance restarts due to a system failure.
  • InstanceFailure.Reboot: The instance restarts due to an instance failure.
NotBefore String Yes The start time of the scheduled event execution time.The time format follows the ISO8601 standard, and the UTC time is used. The format is yyyy-MM-ddTHH:mm:ssZ.

Response parameters

Name Type Description
EventIdSet List of event IDs (EventId) The list of simulated event IDs.


Request example
&InstanceId. 1=i-instance1
&InstanceId. 2=i-instance1
&<Common Request Parameters>
Response example

XML format

JSON format
		"EventId": "e-xhskHun1256xxxx",
		"EventId": "e-xhskHun1257xxxx"

Error codes

Error codes specific to this interface are as follows. For more information, see API Error Center.

Error code Error message HTTP status code Description
InvalidNotBefore.Passed The NotBefore of system event has passed. 400 The specified value for the NotBefore parameter is later than the current time.
InvalidInstanceId.NotFound Cannot find InstanceId. 400 The specified instance ID does not exist.
SimulatedEventLimitExceeded The amount of active simulated system event exceeds limit. 400 The amount of active simulated system events has exceeded the limit in the region.
InstanceIdLimitExceeded The amount of InstanceId specified exceeds limit. 400 The number of specified instance IDs cannot exceed 100 at a time.
MissingParameter The input parameter that is mandatory for processing this request is not supplied. 404 The value for a required parameter is not specified.