Dedicated Host (DDH) allows you to reduce costs when you migrate your businesses to Alibaba Cloud. DDH can meet the strict compliance and regulatory requirements.

A dedicated host provides a dedicated environment for a single tenant to use all resources of a physical server, and provides flexibility to deploy ECS instances. The dedicated host is powered by the virtualization technology that is provided by Alibaba Cloud. The ECS instances on the dedicated host have the same features and performance indexes as the ECS instances on a shared host. For more information about ECS, see What is ECS?

Compared with shared hosts, DDH has the following benefits:
  • Provides dedicated resources.
  • Improves business security.
  • Meets the strict compliance requirements.
  • Allows you to bring your own license (BYOL) to Alibaba Cloud.
  • Allows you to deploy an ECS instance on a specified dedicated host.
  • Provides the dedicated host types that allow you to customize the vCPU-to-memory ratio of an ECS instance.
  • Reduces the deployment cost of ECS instances by using the CPU overprovisioned dedicated host type. For more information about the CPU overprovisioned dedicated host type, see Dedicated host types.
The following table describes the benefit comparisons between the ECS instances on a dedicated host and on a shared host.
Item ECS instances on a dedicated host ECS instances on a shared host
Instance type
  • You can create an ECS instance based on the predefined instance family.
  • You can customize the vCPU-to-memory ratio of an ECS instance on some types of dedicated hosts.

You can create an ECS instance based on the predefined instance family.

Resource isolation

Physical isolation.

CPU, memory, and network resources of a physical server are isolated from other servers. Therefore, physical isolation is a useful method to guarantee a high level of security.

Virtual isolation.

Process, network, and other resources of a virtual server on a physical server are isolated from other virtual servers. However, network, memory, and other resources of the physical server are shared by multiple tenants.

Compliance

Meets the strict regulatory requirements.

The resources of a dedicated host can be used by only one tenant. This meets the regulatory requirements of businesses that require strict supervision, such as financial businesses.

Meets the general regulatory requirements.

The resources of a shared host can be used by multiple tenants.

BYOL

Supported.

The information of a dedicated host, such as the serial number, the number of CPU sockets, and the number of physical CPU cores is provided. You can bring your own licenses to the cloud to reduce migration costs.

Not supported.

The information of a shared host is not provided.

Deployment and migration
  • Allows you to deploy an ECS instance on a specified dedicated host.

    You can create an ECS instance on the specified dedicated host. You can also migrate an ECS instance from a shared host or a dedicated host to the specified dedicated host.

  • Supports automatic deployment of an ECS instance.

    If you do not specify a dedicated host when you create an ECS instance, the system selects a dedicated host to deploy the ECS instance. In addition, if you do not specify a dedicated host when you migrate an ECS instance from a shared host or a dedicated host to another dedicated host, the system also selects a dedicated host to deploy the ECS instance.

The system selects a shared host to deploy an ECS instance.

You cannot specify a host to deploy an ECS instance.