A dedicated host (DDH) is a physical server. It may shut down when a physical failure occurs. To minimize the impact of these failures on your business, Alibaba Cloud supports automatic instance migration when a DDH failure occurs.

You can enable the automatic instance migration feature when or after you create a dedicated host.
  • If you want to enable the automatic instance migration feature when you create a dedicated host, log on to the Elastic Compute Service (ECS) console. In the left-side navigation pane, choose Instances & Images Dedicated Hosts. In the top navigation bar, select a region, and click Create DDH. On the page that appears, select Automatic Instance Migration upon DDH Failure in the DDH Settings section. For information about how to create a dedicated host, see Create a dedicated host.
  • For information about how to modify the configuration of automatic instance migration upon DDH failure, see Modify the automatic instance migration configuration for a DDH.
Notice You cannot perform manual migration of ECS instances on local SSD dedicated hosts such as Local SSD type i2 upon DDH failure. In addition, you cannot perform automatic migration of ECS instances on local SSD dedicated hosts. If local SSD dedicated hosts fail, you can submit a ticket to apply for a manual migration. However, the data in the local disk is lost after migration.

After the automatic instance migration feature is enabled for a dedicated host, the ECS instances on the dedicated host are migrated to another host when a DDH failure occurs. If the automatic instance migration feature is disabled and your dedicated host fails, you can submit a ticket to apply for a new dedicated host.

Notice After all the ECS instances on a failed dedicated host are migrated to another dedicated host, the host ID and the metadata of the ECS instances remain unchanged. The metadata includes the ID, private IP address, and public IP address of each ECS instance. However, the machine ID of the dedicated host is changed.