# Scheduled events for Amazon EC2 instances
To ensure infrastructure reliability and performance, Amazon can schedule events to reboot, stop, and retire your instances. These events do not occur frequently.
If one of your instances will be affected by a scheduled event, Amazon notifies you in advance by email, using the email address that's associated with your Amazon account. The email provides details about the event, such as the start and end dates. Depending on the event type, you might be able to take action to control the timing of the event. Amazon also sends an Amazon Health event, which you can monitor and manage by using Amazon EventBridge. For more information, see [Monitoring events in Amazon Health with Amazon EventBridge](https://docs.amazonaws.cn/health/latest/ug/cloudwatch-events-health.html).
Scheduled events are managed by Amazon. You can't schedule events for your instances. However, you can:
+ View scheduled events for your instances.
+ Reschedule certain scheduled events.
+ Create custom event windows for scheduled events.
+ Take action when an instance is scheduled to reboot, stop, or retire.
To ensure that you receive notifications of scheduled events, verify your contact information on the [Account](https://console.amazonaws.cn/billing/home?#/account) page.
**Note**
When an instance is affected by a scheduled event, and it is part of an Auto Scaling group, Amazon EC2 Auto Scaling eventually replaces it as part of its health checks, with no further action necessary on your part. For more information about the health checks performed by Amazon EC2 Auto Scaling, see [Health checks for instances in an Auto Scaling group](https://docs.amazonaws.cn/autoscaling/ec2/userguide/ec2-auto-scaling-health-checks.html) in the *Amazon EC2 Auto Scaling User Guide*.
## Types of scheduled events
Amazon EC2 can create the following types of scheduled events for your instances, where the event occurs at a scheduled time:
| Event type | Event code | Event action |
| --- | --- | --- |
| Instance stop | instance-stop | At the scheduled time, the instance is stopped. When you start it again, it's migrated to a new host. Applies only to instances with an Amazon EBS root volume. |
| Instance retirement | instance-retirement | At the scheduled time, the instance is stopped if it has an Amazon EBS root volume, or terminated if it has an instance store root volume. |
| Instance reboot | instance-reboot | At the scheduled time, the instance is rebooted. The instance stays on the host, and during the reboot, the host undergoes maintenance. This is known as an in-place reboot. |
| System reboot | system-reboot | At the scheduled time, the instance is rebooted and migrated to a new host. This is known as a reboot migration. |
| System maintenance | system-maintenance | At the scheduled time, the instance might be temporarily affected by network maintenance or power maintenance. |
## Determine the event type
You can check what type of event is scheduled for your instance.
------
#### [ Console ]
**To determine the event type**
1. Open the Amazon EC2 console at [https://console.amazonaws.cn/ec2/](https://console.amazonaws.cn/ec2/).
1. In the navigation pane, choose **Events**.
1. In the table, the event code appears in the **Event type** column.
1. To filter the table to show only the events for instances, in the search field choose **Resource type: instance** from the filter list.
------
#### [ Amazon CLI ]
**To determine the event type for an instance**
Use the [describe-instance-status](https://docs.amazonaws.cn/cli/latest/reference/ec2/describe-instance-status.html) command. If the instance has an associated scheduled event, the output provides information about the scheduled event.
```
aws ec2 describe-instance-status \
--instance-ids i-1234567890abcdef0 \
--query InstanceStatuses[].Events
```
The following is example output. The scheduled event code is `system-reboot`.
```
[
"Events": [
{
"InstanceEventId": "instance-event-0d59937288b749b32",
"Code": "system-reboot",
"Description": "The instance is scheduled for a reboot",
"NotAfter": "2020-03-14T22:00:00.000Z",
"NotBefore": "2020-03-14T20:00:00.000Z",
"NotBeforeDeadline": "2020-04-05T11:00:00.000Z"
}
]
]
```
------
#### [ PowerShell ]
**To determine the event type for an instance**
Use the [Get-EC2InstanceStatus](https://docs.amazonaws.cn/powershell/latest/reference/items/Get-EC2InstanceStatus.html) cmdlet. If the instance has an associated scheduled event, the output provides information about the scheduled event.
```
(Get-EC2InstanceStatus `
-InstanceId i-1234567890abcdef0).Events
```
The following is example output. The scheduled event code is `system-reboot`.
```
Code : system-reboot
Description : The instance is scheduled for a reboot
InstanceEventId : instance-event-0d59937288b749b32
NotAfter : 2020-03-14T22:00:00.000Z
NotBefore : 2020-03-14T20:00:00.000Z
NotBeforeDeadline : 2020-04-05T11:00:00.000Z
```
------
**Topics**
+ [Types of scheduled events](#types-of-scheduled-events)
+ [Determine the event type](#scheduled-event-type)
+ [Manage Amazon EC2 instances scheduled to stop or retire](schedevents_actions_retire.md)
+ [Manage Amazon EC2 instances scheduled for reboot](schedevents_actions_reboot.md)
+ [Manage Amazon EC2 instances scheduled for maintenance](schedevents_actions_maintenance.md)
+ [View scheduled events that affect your Amazon EC2 instances](viewing_scheduled_events.md)
+ [Reschedule a scheduled event for an EC2 instance](reschedule-event.md)
+ [Create custom event windows for scheduled events that affect your Amazon EC2 instances](event-windows.md)