Dedicated Host (DDH) has the following limits. ECS resource limits also apply to ECS instances on dedicated hosts — see ECS limits for details.
| Item | Limit | Adjustable |
|---|---|---|
| Creating dedicated hosts | Complete real-name verification before creating dedicated hosts in the Chinese mainland. You must complete identity verification before you create a DDH in the Chinese mainland. | No |
| Supported network types | Virtual private clouds (VPCs) only. See What is a VPC? | No |
| Maximum disks per dedicated host | 200 | No |
| Billing methods | Subscription dedicated hosts support pay-as-you-go and subscription ECS instances. | No |
| Subscription ECS instance expiration | The expiration time of a subscription ECS instance cannot be later than that of its dedicated host. This applies when creating, renewing, or switching an ECS instance from pay-as-you-go to subscription. If the auto-renewal period would exceed the dedicated host's expiration time, auto-renewal fails. | No |
| Changing a dedicated host's billing method | Pay-as-you-go to subscription only. You cannot change the billing method from subscription to pay-as-you-go. | No |
| Migrating ECS instances between a shared host and a dedicated host | Pay-as-you-go ECS instances only. Subscription and preemptible instances cannot be migrated. | No |
| Migrating ECS instances between dedicated hosts | Same dedicated host type only, within the same Alibaba Cloud account. You cannot migrate ECS instances between dedicated hosts of the local SSD type. See Dedicated host types. | No |
| Automatic failover | ECS instances on local SSD dedicated hosts cannot be automatically migrated when a host failure occurs. | No |
| Windows images | Outside the Chinese mainland, Windows images cannot be used on ddh.c6s, ddh.g6s, or ddh.r6s dedicated hosts. | No |
| Maximum ECS instances per dedicated host | Up to 150 on: g6t, c6t, g6s, c6s, r6s, g6, c6, r6, i2. Up to 100 on: g5, c5, r5, v5, g5se, g5ne. | No |