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Elastic Compute Service

Overview

What is DDH

Overview

VolcanoEngine Dedicated Host (DDH) is a cloud server with physical resources exclusively for a single user. You can deploy ECS instances on a dedicated host to meet high requirements for resource exclusivity, resource isolation, security, and performance.

As the sole user of a DDH, you do not need to share any physical resources of the cloud server with other users. In addition, Bring Your Own License (BYOL) is supported. Therefore, you can continue to use your previous server-side software licenses when migrating your business to a DDH. This reduces the cost of migrating your business to the cloud and improves flexibility of ECS instance management.

Related concepts

Term	Description
DDH	A cloud host that provides exclusive physical resources for a single user. As the sole user of this cloud host, you can independently plan the physical resources and do not need to share them with other users.
Shared host	A cloud host that provides shared physical resources for multiple users, that is, the physical server used to deploy standard ECS instances. The host machine where the instance resides can only be assigned by the system, and cannot be selected by yourself.
CPU oversubscription ratio	For scenarios with low CPU load requirements, you can increase the count of available vCPUs by configuring a CPU oversubscription ratio for your DDH. This allows you to deploy more instances of the same instance type with lower deployment costs. For more information, refer to change CPU oversubscription ratio.
Automatic deployment	After you enable "Allow automatic deployment" for DDH, the system places it into the resource pool for automatically deployed instances. Therefore, when creating an instance, you do not need to specify a DDH. Then, the system will select a DDH from the automatic deployment pool to deploy the instance, improving the flexibility of resource deployment. For more information, refer to Setting automatic deployment.
Associated host	Applicable for instances with Economical Mode enabled. After you associate a host with an ECS instance in Economical Mode and restart the instance, it will still be deployed on the current host. For more information, refer to Associating instance with DDH.
Region and availability zone	The physical location of the data center where the physical server corresponding to DDH is located. To reduce access latency and accelerate downloads, we recommend selecting the region closest to you or your target users. For more information, refer to Regions and availability zones.

DDH and shared host

The comparison between DDH and shared host is shown in the following figure.

As shown in the figure above (the left figure), as the sole user of a DDH, you do not need to share the physical resources of the host with other users (the right figure). You can obtain the usage and physical attributes of the DDH resources (such as physical cores, number of sockets, CPU type, and memory size), and create ECS instances with specified type based on the DDH type.

Last updated: 2026.01.16 19:03:59