This topic describes the limits on ECS product features and service performance and provides the method to apply for a higher quota.
When you use ECS, the following limits apply:
- ECS does not support virtual application installation or revirtualization (such as installation of VMware Workstation). Currently, only ECS Bare Metal Instance and Super Computing Clusters support revirtualization.
- ECS does not support sound card applications.
- ECS does not support external hardware devices directly (such as dongles, USB drives, or external hard drives). Instead, it supports a software protection dongle or two-step verification with dynamic passwords.
- ECS does not support IP address translation services such as SNAT. Instead, it supports a VPN or proxy.
- ECS does not support multicast protocols. If multicasting services are required, we recommend that you use point-to-point unicast instead.
- Currently, Log Service does not support 32-bit Linux ECS instances. For information about regions that support Log Service, see Service endpoint. For information about operating systems that support Log Service, see Overview.
In addition to the preceding limits, the following table details further limits of ECS and states whether you can open a ticket to request changing the limits.
ECS instances
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| Permission to create instances | Complete real-name registration before creating ECS instances in any Mainland China regions. | No |
| Instance types for which you can create Pay-As-You-Go instances | Instance types with less than 16 vCPUs | Yes |
| vCPU quota of Pay-As-You-Go instances in each region for a single account |
50 vCPUs You can click Privileges & Quota Management on the Overview page of the ECS console to view the quota. |
Yes |
| vCPU quota of preemptible instances in each region for a single account | Up to 50 vCPUs are allowed after you open a ticket to obtain the permission.
You can click Privileges & Quota Management on the Overview page of the ECS console to view the quota. |
Yes |
| Quota of launch templates in each region for a single account | 30 | No |
| Quota of versions of a single launch template | 30 | No |
| Switch from Pay-As-You-Go to Subscription | The following instance types (families) are not supported: t1, s1, s2, s3, c1, c2, m1, m2, n1, n2, and e3. | No |
| Switch from Subscription to Pay-As-You-Go |
|
No |
Block storage
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| Create Pay-As-You-Go cloud disks | Complete real-name registration before creating cloud disks in any Mainland China regions. | No |
| Quota of Pay-As-You-Go cloud disks in all regions for a single account | Number of Pay-As-You-Go instances in all regions under the user account × 5 | Yes |
| Quota of system disks for a single instance | 1 | No |
| Quota of data disks for a single instance | 16 (including cloud disks and Shared Block Storage) | No |
| Quota of instances to which a single Shared Block Storage can be attached | 8 | No |
| Quota of Shared Block Storage in all regions for a single account | 10 | Yes |
| Capacity of a single Basic Cloud Disk | 5 GiB−2,000 GiB | No |
| Capacity of a single SSD Cloud Disk | 20 GiB−32,768 GiB | No |
| Capacity of a single Ultra Cloud Disk | 20 GiB−32,768 GiB | No |
| Capacity of a single local SSD disk | 5 GiB−800 GiB | No |
| Capacity of local SSD disks for a single instance | 1,024 GiB | No |
| Capacity of a single local NVMe SSD disk | 1,456 GiB | No |
| Capacity of local NVMe SSD disks for a single instance | 2,912 GiB | No |
| Capacity of a single local SATA HDD disk | 5,500 GiB | No |
| Capacity of local SATA HDD disks for a single instance | 154,000 GiB | No |
| Capacity of a single SSD Shared Block Storage | 32,768 GiB | No |
| Capacity of SSD Shared Block Storage for a single instance | 128 TiB | No |
| Capacity of a single Ultra Shared Block Storage | 32,768 GiB | No |
| Capacity of Ultra Shared Block Storage for a single instance | 128 TiB | No |
| Capacity of a single ESSD disk | 32,768 GiB | No |
| Capacity of a single system disk |
|
No |
| Capacity of a single data disk |
|
No |
| Attach a new local disk to an instance with local disks | This feature is not supported. | No |
| Change configuration of an instance with local disks | Only bandwidth changes are allowed. | No |
| System disk mount points | /dev/xvda | No |
| Data disk mount points | /dev/xvd[b-z] | No |
Note Block storage capacity is measured in binary units. 1 KiB is 1,024 bytes. 1 MiB is 1,024 KiB. 1 GiB is 1,024 MiB. 1 TiB is 1,024 GiB.
Snapshots
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| The number of snapshots that can be created for each cloud disk and Shared Block Storage | 64 | No |
Images
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| Quota of custom images in a region for each account | 100 | Yes |
| Maximum number of users with whom a single image can be shared | 50 | Yes |
| Usage of images on instance types | 32-bit images are not supported on an instance with 4 GiB or more RAM. | No |
Key pairs
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| Quota of key pairs in a region for each account | 500 | No |
| Instance types supporting key pairs | All instance types except non-I/O optimized instance types in Generation I | No |
| Images supporting key pairs | Linux images only | No |
Internet bandwidth
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| Maximum inbound Internet bandwidth | 200 Mbit/s | No |
| Maximum outbound Internet bandwidth |
|
No |
| Change the assigned Internet address for a single instance | The instance has existed for less than six hours. You can change the Internet address of an instance three times. | No |
Security groups
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| Quota of security groups in a region for each account |
100 You can click Privileges & Quota Management on the Overview page of the ECS console to view the quota. |
Yes |
| Quota of instances/IP addresses for a single security group |
|
No |
| Quota of security group rules for each ENI of a single instance | 500 | No |
| Quota of security groups to which each ENI belongs for a single instance | 5 | Open a ticket to raise the upper limit to 10 or 16 |
| Quota of rules for a single security group | 100 | No. It decreases as the security group quota increases. For detailed restrictions, see Security groups. |
| Port | For the outbound Internet traffic, the default STMP port is 25, which is disabled by default and cannot be enabled through security group rules. | Open a ticket to enable it. For more information, see Request for enabling TCP port 25 |
Deployment sets
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| Quota of deployment sets in a region for each account | 2 | No |
| The number of instances that can be included in a deployment set | Seven instances are allowed in each zone. The number of instances allowed in a region equals the number of zones × 7. | No |
| Instance types that can be created in a deployment set | c5, g5, hfc5, hfg5, r5, se1ne, sn1ne, and sn2ne | No |
Cloud assistants
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| Quota of cloud assistant scripts in a region for each account | 100 | Yes |
| Quota to invoke cloud assistant scripts in a region for each account | 500 | Yes |
ENIs
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| Quota of ENIs in a region for each account |
100 You can click Privileges & Quota Management on the Overview page of the ECS console to view the quota. |
Yes |
Tags
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| Quota of tags that can be bound to a single instance | 20 | No |
API
| Item | Limit | Can I open a ticket to change the limit? |
|---|---|---|
| Quota of CreateInstance calls | 200 times per minute | Yes |
Note For the limits of VPC products, see Limits.