ECS does not support:
- Sound card applications.
- The installation of external hardware devices such as hardware dongles, USB drives, external hard drives, and the USB security keys issued by banks.
- SNAT and other IP packet address translation services. Achieve this using an external VPN or proxy.
- Multicast protocol. If multicasting services are required, unicast point-to-point method is recommended.
- Virtual application installation or subsequent virtualization such as when using VMware.
Besides the preceding limits, using ECS has the follwing limits. Unless otherwise specified, all the resource limits listed in the table are for one region.
|Restricted item||Parameter||To apply for an exception or unlock configuration rights|
|User creation of ECS resources||N/A||Users must undergo real-name registration|
|Default Pay-As-You-Go instance quota in all regions||10||Request increase by ticket|
|Disk quota within a single instance||17, including one system disk and 16 data disks||No higher configurations exist|
|Support for Pay-As-You-Go ephemeral disks||Supported||For APIs, open a ticket. Other types do not support this disk type|
|Capacity of a single ephemeral disk||20 to 1,024 GB||No higher configurations exist|
|Total ephemeral disk size for a single instance||2,048 GB||No higher configurations exist|
|Number of snapshots||(Number of disks)*64||No higher configurations exist|
|Capacity of a single basic cloud disk||5 to 2,000 GB||No higher configurations exist|
|Number of accounts to share a single custom image with||50||No higher configurations exist|
|List of available public images||List of images for sale on the official website||Common users cannot change; for others, open a ticket to add other images|
|Number of Elastic Network Interfaces (ENI)||100||No higher configurations exist|
|Available inbound bandwidth for Internet access||Up to 200 Mbps||No higher configurations exist|
|Available outbound bandwidth for Internet access||Up to 200 Mbps||No higher configurations exist|
|Number of instances allowed in a single security group||1,000||No higher configurations exist|
|Number of authorization rules for a single security group||100||No higher configurations exist|
|Security group quota||100||Request increase by ticket|
|Maximum number of security groups that a single instance can belong to||5||No higher configurations exist|
|Restrictions on image and instance types||Instances with 4 GB or more of memory cannot use 32-bit images||N/A|
|Adding new disks for ephemeral disk instances||Not supported||N/A|
|Changing the configuration of an instance with ephemeral disks||Bandwidth is adjustable||No exceptions (cloud disks can be used for attachment)|
|Relationship between the system disk and data disk||If the system disk is a cloud disk, all data disks must be cloud disks||N/A|
|Total number of Pay-As-You-Go cloud disks that can be purchased||ECS Instance Quota * 5||Request increase by ticket|
|Basic cloud disk capacity||5 to 2,000 GB||No higher configurations exist|
|User restrictions for the creation of Pay-As-You-Go cloud disks||Users must pass real-name registration (for buy only)||N/A|
|Range of system disk attaching points||/dev/xvda||N/A|
|Range of data disk attaching points||/dev/xvd[b-z]||N/A|
|Capacity of a single SSD Cloud Disk||20 to 2,048 GB||No higher configurations exist|
|Capacity of a single ultra Cloud Disk||20 to 2,048 GB||No higher configurations exist|
|Zones in which users may create instances||1 online zone||Request increase by ticket|
|Zones in which users may create disks||The zone combinations in which users may create instances and the zones where instances remain after overlap removal||N/A|
|Default Pay-As-You-Go instance types||ecs.t1.small (single-core 1 GB)||Request change by ticket|
|ecs.s1.small (single-core 2 GB)|
|ecs.s1.medium (single-core 4 GB)|
|ecs.s2.small (dual-core 2 GB)|
|ecs.s2.large (dual-core 4 GB)|
|ecs.s2.xlarge (dual-core 8 GB)|
|ecs.s3.medium (quad-core 4 GB)|
|ecs.s3.large (quad-core 8 GB)|
|ecs.m1.medium (quad-core 16 GB)|
For limits of VPC, see Limits in VPC Product Introduction.