Ringkasan fitur produk yang komprehensif - Dedicated Host - Alibaba Cloud - Dedicated Host

Dedicated Host adalah server fisik single-tenant yang berjalan di atas stack virtualisasi Alibaba Cloud. Topik ini menjelaskan fitur-fitur Dedicated Host (DDH).

Isolasi fisik

DDH menyediakan fitur isolasi fisik:

Sumber daya CPU, memori, dan jaringan dari Dedicated Host secara fisik terisolasi dari host lainnya, sehingga menjamin tingkat keamanan yang tinggi. Sebagai satu-satunya penyewa host tersebut, Anda tidak berbagi sumber daya fisik dengan penyewa lain.
Anda dapat memperoleh atribut fisik host, termasuk jumlah core CPU fisik, ukuran memori, jumlah vCPU, dan kode mesin unik, serta melihat penggunaan sumber daya secara real time.

Penyebaran otomatis

Setelah Anda mengaktifkan penyebaran otomatis untuk Dedicated Host, host tersebut akan masuk ke dalam kolam sumber daya Akun Alibaba Cloud Anda untuk penyebaran otomatis. Saat membuat Instance ECS, Anda tidak perlu menentukan Dedicated Host tertentu—sistem akan memilih Dedicated Host dari kolam sumber daya untuk menempatkan instance tersebut. Untuk informasi selengkapnya, lihat Aktifkan penyebaran otomatis. Fitur ini memungkinkan Anda menyebar bisnis secara fleksibel.

Tabel berikut menjelaskan skenario penggunaan penyebaran otomatis.

Scenario	Operation	Result	References
Create an ECS instance	Specify a dedicated host	The ECS instance is deployed on the dedicated host.	Console operation: Create an instance with Custom Launch API operation: CreateInstance or RunInstances.
Create an ECS instance	Select Autoplacement	The ECS instance is automatically deployed on a dedicated host.
Migrate an ECS instance from a shared host to a dedicated host	Specify a dedicated host	The ECS instance is deployed on the dedicated host.	Console operation: Migrate an ECS instance from a shared host to a DDH API operation: ModifyInstanceDeployment
	Do not specify a dedicated host	The ECS instance is automatically deployed on a dedicated host.	Console operation: The console does not support this scenario. API operation: ModifyInstanceDeployment
Migrate an ECS instance between two dedicated hosts	Specify a dedicated host	The ECS instance is deployed on the dedicated host.	Console operation: Migrate an ECS instance between DDHs API operation: ModifyInstanceDeployment
Migrate an ECS instance between two dedicated hosts	Do not specify a dedicated host	The ECS instance is automatically deployed on a dedicated host. Catatan If the dedicated host where the ECS instance resides allows automatic deployment and has the most available resources, the instance is still deployed on the dedicated host.	Console operation: The console does not support this scenario. API operation: ModifyInstanceDeployment

Rasio overcommit CPU

Anda dapat mengonfigurasi rasio overcommit CPU untuk Dedicated Host tipe g6s, c6s, dan r6s. Jika Anda mengubah rasio overcommit CPU Dedicated Host, jumlah vCPU yang tersedia juga akan berubah. Rasio overcommit CPU Dedicated Host dihitung berdasarkan rumus berikut: Jumlah vCPU yang tersedia pada Dedicated Host = Jumlah core CPU × 2 × rasio overcommit CPU. Pada skenario yang memerlukan stabilitas CPU lebih rendah atau beban CPU tidak berat, Anda dapat meningkatkan rasio overcommit CPU Dedicated Host sehingga jumlah vCPU yang tersedia bertambah, memungkinkan penyebaran lebih banyak Instance ECS dengan spesifikasi yang sama dan mengurangi biaya penyebaran per unit. Untuk informasi selengkapnya, lihat Setel rasio overcommit CPU.

Migrasi instans otomatis saat terjadi kegagalan perangkat keras

Dedicated Host didasarkan pada server fisik dan dapat mati jika terjadi kegagalan perangkat keras. Untuk meminimalkan dampak kegagalan perangkat keras terhadap bisnis Anda, Alibaba Cloud mendukung migrasi instans otomatis saat terjadi kegagalan perangkat keras. Jika terjadi kegagalan perangkat keras setelah Anda mengaktifkan fitur ini untuk Dedicated Host, Instance ECS pada Dedicated Host tersebut akan dimigrasikan ke host lain.

Tabel berikut menjelaskan skenario penggunaan penyebaran otomatis.

Scenario	Operation
Enable automatic instance migration for a dedicated host.	When you create the dedicated host, select Automatic Instance Migration upon DDH Failure in the DDH Settings section of the Create DDH page. For more information, see Create a DDH. For information about how to enable automatic instance migration for an existing dedicated host, see Configure auto failover.
A dedicated host has potential risks.	Migrate the dedicated host to another dedicated host to protect your services. For more information, see Migrate a dedicated host with failure risks.
A dedicated host fails.	If automatic instance migration is enabled for the dedicated host, the ECS instances on the dedicated host are migrated to another host. If automatic instance migration is not enabled for the dedicated host, submit a ticket to apply for a new dedicated host.

Penting

You cannot perform manual migration of ECS instances on local SSD dedicated hosts such as Local SSD type i2 upon hardware failures. 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 manual migration. However, the data in the local disk is lost after manual migration.
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.

Asosiasi host

Fitur asosiasi host cocok untuk Instance ECS yang telah mengaktifkan mode hemat. Meskipun instans memasuki status Stopped, instans tersebut tetap ditempatkan pada server fisik asalnya. Fitur ini juga membantu Anda mempertahankan metode penempatan yang sama untuk Instance ECS.

Tabel berikut menjelaskan skenario penggunaan asosiasi host.

Scenario	Operation	Result
Stop and restart an ECS instance that has enabled the economical mode	Enable the host association feature. For more information, see Associate an ECS instance with a DDH.	The ECS instance is still deployed on the original dedicated host. If the available resources of the dedicated host are insufficient, the instance fails to be restarted.
	Disable the host association feature. For more information, see Associate an ECS instance with a DDH.	ECS first attempts to deploy the ECS instance on the original dedicated host. If the available resources of the dedicated host are insufficient, ECS deploys the instance on another dedicated host.

Migrasi Instance ECS

Anda dapat memigrasikan Instance ECS antara dua Dedicated Host atau antara host bersama dan Dedicated Host.

Perbedaan antara Instance ECS pada Dedicated Host dan Instance ECS pada host bersama

Fitur Instance ECS yang ditempatkan pada Dedicated Host berbeda dengan Instance ECS yang ditempatkan pada host bersama. Tabel berikut mencantumkan perbedaan tersebut.

Item	ECS instances on a dedicated host	ECS instances on a shared host
Network Type	Virtual private clouds (VPCs) are supported.	VPCs and the classic network are supported. For more information, see Network types.
Billable item	See Billing for ECS resources on DDHs.	See Billing overview.
Billing method	Subscription and pay-as-you-go are supported.	Subscription, pay-as-you-go, preemptible instances, and reserved instances are supported.
Renewal	When you specify the renewal period, the expiration date of the instance cannot be later than that of the subscription dedicated host. For more information, see Limits.	You can specify the renewal period based on your business requirements.
Economical mode	If an instance is stopped after the economical mode is enabled, the resources of the dedicated host are released. These resources include the vCPUs and memory. Resources are reallocated to the dedicated host after the instance is restarted. For more information, see Dedicated Host billing.	See Economical mode.
Switch the billing method from pay-as-you-go to subscription	Before you switch the billing method of an instance, the instance must meet the prerequisites. The feature is applicable only to the instances on a pay-as-you-go dedicated host. After the billing method of an ECS instance is switched to subscription, the expiration date of the instance cannot be later than that of the dedicated host.	Before you switch the billing method of an instance, the instance must meet the prerequisites. For more information, see Change the billing method from pay-as-you-go to subscription.
Create an ECS instance	See Create ECS instances on a dedicated host.	See Create an instance with Custom Launch.
ECS instance type	You can create an ECS instance based on a predefined instance family. You can customize the vCPU-to-memory ratio of an ECS instance on multiple types of dedicated hosts. For more information, see Specifications.	You can create an ECS instance based on a predefined instance family. For more information, see Instance family overview.
Upgrade or downgrade an ECS instance	See Upgrade or downgrade subscription instance types.	See Change the instance type.
Release an ECS instance	If you do not renew expired dedicated hosts, the ECS instances on the hosts are automatically released.	Pay-as-you-go ECS instances can be manually or automatically released. For more information, see Release an instance. If you do not renew a subscription ECS instance after it expires, the instance is automatically released. If a pay-as-you-go ECS instance has overdue payments and your account has insufficient balance, the ECS instance is automatically released.
Adjust public bandwidth	See Upgrade or downgrade the public bandwidth of a subscription instance.	See Modify the maximum public bandwidth.