Configure the host maintenance setting for an Amazon EC2 Dedicated Host

Enable host maintenance to ensure that your instances running on a Dedicated Host are automatically recovered onto a new Dedicated Host during a scheduled maintenance event.

If you disable host maintenance, you receive an email notification to evict the degraded host and manually migrate your instances to another host within 28 days. A replacement host is allocated if you have Dedicated Host reservation. After 28 days, the instances running on the degraded host are terminated, and the host is released automatically.