Elastic Compute Service (ECS) enforces limits on product features, service performance, and associated quotas. Some limits are fixed; others can be increased. Review these limits before deployment to plan your resources and avoid unexpected constraints.
Each table in this document has three columns: Restriction item (the feature or quota subject to a limit), Limit (the specific constraint, including a quota ID if applicable), and How to increase quota (the method to raise the limit, or "Not applicable" if the limit is fixed). Use the quota ID to look up the current value in Quota Center.
Instances
Restriction item | Limit | How to increase quota |
vCPU quotas | Per instance family, per region, per billing method (subscription, pay-as-you-go, or spot). See vCPU quotas. | |
GPU and vGPU quotas | Per instance family, per region, per billing method (subscription, pay-as-you-go, or spot). See GPU and vGPU quotas. | |
Maximum subscription instances per purchase (single account, single region) | Quota ID: | Not applicable |
Convert pay-as-you-go to subscription | No limit on the number of instances or the quota. Discontinued instance types cannot be converted. See Convert a pay-as-you-go instance to a subscription instance. | Not applicable |
Convert subscription to pay-as-you-go | Converting a subscription instance generates a refund that counts against your monthly refund limit. When the limit is reached, no further conversions are possible until the limit resets on the first day of the next month. The current limit is shown on the conversion page. See Convert a subscription instance to a pay-as-you-go instance. | Not applicable |
Secondary virtualization | Only ECS Bare Metal Instances and Super Computing Clusters (SCCs) support secondary virtualization. Other instance families do not support installing virtualization software or secondary virtualization. | Not applicable |
Sound card applications | Not supported. | Not applicable |
External hardware devices | Cannot attach external hardware devices directly, such as hardware dongles, USB drives, external hard drives, or bank U-Keys. Use software dongles or dynamic passwords for secondary authentication instead. | Not applicable |
Multicast protocol | Not supported. For one-to-many communication, use unicast point-to-point communication instead. | Not applicable |
Website ICP filing | Requires a subscription instance with a duration of three months or more. Each ECS instance supports ICP filings for up to five websites or apps. See Check the server for ICP filing. | Not applicable |
Software licenses | Migrating an ECS instance may change its hardware information and invalidate licenses bound to hardware. | Not applicable |
vCPU quotas
GPU and vGPU quotas
Image
Restriction item | Limit | How to increase quota |
Maximum custom images per account per region | Quota ID: | |
Maximum users a custom image can be shared with | Quota ID: | |
Image and instance type compatibility | Instance types with 4 GiB or more of memory cannot use 32-bit images. | Not applicable |
For more information, see Image overview.
Block storage
Block storage capacity is measured in binary units (base 1024). For example, 1 GiB equals 1,024 MiB.
Restriction item | Limit | How to increase quota |
System disks per instance | 1 | Not applicable |
Data disks per instance | Varies by instance type. Query the limit using the DescribeInstanceTypes API. When creating an instance, specify up to 1 system disk and 64 data disks; the actual limit is shown in the console. Attach additional data disks after instance creation. See Instance families. | Not applicable |
Disk capacity quota per account per region and zone | Varies by disk type. See View or increase block storage quotas. | |
Basic disk capacity | 5 GiB–2,000 GiB | Not applicable |
Standard SSD capacity | 20 GiB–32,768 GiB | Not applicable |
Ultra disk capacity | 20 GiB–32,768 GiB | Not applicable |
ESSD capacity | PL0: 1–65,536 GiB; PL1: 20–65,536 GiB; PL2: 461–65,536 GiB; PL3: 1,261–65,536 GiB | Not applicable |
ESSD AutoPL disk capacity | 1 GiB–65,536 GiB | Not applicable |
ESSD Entry disk capacity | 10 GiB–32,768 GiB | Not applicable |
Regional Enterprise SSD (ESSD) capacity | 1 GiB–65,536 GiB | Not applicable |
Local SSD capacity | Depends on instance type; 5 GiB–7,152 GiB | Not applicable |
Total local SSD capacity per instance | Depends on instance type; up to 8 × 7,152 GiB | Not applicable |
Elastic ephemeral disk capacity | 64 GiB–8,192 GiB | Not applicable |
System disk capacity | Windows Server: 40 GiB–2,048 GiB; FreeBSD: 30 GiB–2,048 GiB; other Linux: 20 GiB–2,048 GiB. When a basic disk is used as a system disk, the maximum capacity is 500 GiB. | Not applicable |
Attach new local disks to an instance that already has local disks | Not supported. | Not applicable |
Configuration changes for instances with local disks | Only bandwidth changes are supported. | Not applicable |
Linux system disk mount point |
| Not applicable |
Linux data disk mount points | 1–25 data disks: | Not applicable |
For more information, see Block storage overview.
Snapshots
Restriction item | Limit | How to increase quota |
Manual snapshots per disk | 2,000 | Not applicable |
Automatic snapshots per disk | 2,000 | Not applicable |
Archived snapshots per disk | 10,000 | Not applicable |
Automatic snapshot policies per account per region | 100 | Not applicable |
Automatic snapshot policies per disk | 10 | Not applicable |
Concurrent snapshots per disk (ESSD series: ESSDs, ESSD AutoPL, ESSD Entry, Regional ESSDs) | 10 | Not applicable |
Concurrent snapshots per disk (legacy disks: standard SSDs, ultra disks, basic disks) | 1 | Not applicable |
Concurrent archived snapshots per disk | 10 | Not applicable |
Snapshot support by disk type | Snapshots cannot be created for local disks or elastic ephemeral disks. The snapshot-consistent group feature requires ESSD series disks with multi-attach disabled. The instant access feature is available only for ESSD series disks (ESSDs, ESSD AutoPL, ESSD Entry, and Regional ESSDs). See Multi-attach and Snapshot instant access. | Not applicable |
Download or export snapshots | Not supported. To get snapshot data, create a custom image from a snapshot and then export the image. | Not applicable |
Concurrent manual and automatic snapshot creation | ESSD series disks (ESSDs, ESSD AutoPL, ESSD Entry, and Regional ESSDs) support concurrent creation of manual and automatic snapshots. However, the number of concurrent snapshots is subject to the concurrent snapshot limit. If the limit is reached, subsequent snapshot creation tasks fail. Legacy disks (standard SSDs, ultra disks, and basic disks) have the following constraints: (1) Concurrent creation of manual and automatic snapshots is not supported. (2) At the scheduled time when an automatic snapshot is due to be created, if a snapshot (manual or automatic) is already being created for the disk, the system skips that scheduled snapshot and tries again at the next scheduled time. (3) If an automatic snapshot is being created for a disk, you must wait for it to complete before you can manually create a snapshot. | Not applicable |
For more information, see Snapshot overview.
Public bandwidth
Account-level bandwidth limits
The following limits apply to all pay-as-you-go and spot instances using pay-by-bandwidth in a single Alibaba Cloud account within a single region.
To request a higher limit, use quota ID q_internet-bandwidth-pay-by-bandwidth-of-postpaid-instance. See View or increase ECS quotas.Region | Limit |
China (Beijing), China (Shanghai), China (Hangzhou), and China (Shenzhen) | 50 Gbps |
China (Hong Kong) and Singapore | 20 Gbps |
Other regions | 10 Gbps |
Starting November 27, 2020, account-level rate limiting applies when creating or changing instance configurations:
To request a higher peak bandwidth, submit a ticket.
Total actual peak bandwidth of all pay-by-traffic instances in a single region: 5 Gbps
Total actual peak bandwidth of all pay-by-bandwidth instances in a single region: 50 Gbps
Per-instance bandwidth limits
For pay-by-traffic instances, inbound and outbound peak bandwidth values are upper limits and are not guaranteed. During resource contention, peak bandwidth may be reduced. For guaranteed bandwidth, use pay-by-bandwidth.
Pay-by-bandwidth: 200 Mbit/s
Pay-by-bandwidth:
Subscription instances: 200 Mbit/s
Pay-as-you-go instances: 100 Mbit/s
Pay-by-traffic:
Subscription instances: 200 Mbit/s
Pay-as-you-go instances: 100 Mbit/s
Pay-by-traffic: 100 Mbit/s
Restriction item | Limit | How to increase quota |
Peak inbound bandwidth per instance | If the outbound peak bandwidth is 10 Mbit/s or less, Alibaba Cloud allocates 10 Mbit/s inbound. If the outbound peak bandwidth exceeds 10 Mbit/s, inbound bandwidth equals the outbound bandwidth. | Not applicable |
Peak outbound bandwidth per instance | Pay-by-traffic: subscription instances: 200 Mbit/s; pay-as-you-go instances: 100 Mbit/s. Pay-by-bandwidth: 200 Mbit/s. The actual limit also depends on the instance type's Baseline network bandwidth listed in Instance families. Some instance types (such as ecs.t6-c4m1.large, ecs.t6-c2m1.large, ecs.t6-c1m1.large, and ecs.t6-c1m4.large) are limited to 80 Mbit/s by their baseline network bandwidth. | Not applicable |
Public IP address replacement per instance | Replace the public IP address within the first six hours after instance creation, up to three times total. | Not applicable |
For more information, see Public bandwidth.
Elastic Network Interfaces
Restriction item | Limit | How to increase quota |
Maximum ENIs (secondary ENIs) per account per region | Quota ID: | |
VPC and zone requirements | An instance and its attached Elastic Network Interfaces (ENIs) must be in the same VPC and zone. Multiple ENIs on the same instance can belong to different vSwitches within that VPC. Attaching two or more ENIs from the same vSwitch to an instance may cause asymmetric routing. To maximize VPC instance utilization and enable traffic failover, assign secondary private IP addresses to ENIs instead. See Secondary private IP addresses. | Not applicable |
Maximum ENIs per instance | Determined by instance type. See the Elastic network interface column in Instance families. | Not applicable |
For more information, see ENI overview.
Prefix lists
Restriction item | Limit | How to increase quota |
Maximum prefix lists per account per region | 100 | Not applicable |
Maximum entries in a single prefix list | 200 | Not applicable |
Maximum associated instances per prefix list | 1,000 | Not applicable |
For more information, see Prefix list overview.
Security groups
Restriction | Basic security group | Enterprise security group |
Maximum security groups per account per region | Quota ID: | Same as basic security groups |
Security groups per ENI | 10 | Same as basic security groups |
Maximum rules (inbound + outbound) across all security groups per ENI | 1,000 | Same as basic security groups |
Rules that use another security group as the authorization object | 20 | 0. Enterprise security groups do not support security group authorization objects, and cannot be used as authorization objects in other security group rules. |
ECS instances per VPC security group | Not fixed; depends on the number of private IP addresses the security group can contain. | No limit |
Maximum private IP addresses per VPC security group per account per region | 6,000. IP address count includes all address types on associated ENIs (primary private IPv4, IPv6, secondary private IPv4, IPv4 prefixes, and IPv6 prefixes). If you need more than 6,000 private IP addresses to communicate over the internal network, distribute ECS instances across multiple security groups and allow inter-group access. View this quota using quota ID | 65,536. IP address count represents the total number of ENIs (primary and secondary) associated with the security group. |
Public port 25 | Restricted by default for security reasons. Use SSL-encrypted port 465 to send emails instead. | Same as basic security groups |
For more information, see Security group overview.
Reserved instances
Restriction item | Limit | How to increase quota |
Total regional reserved instances per account (all regions combined) | 20 | |
Zonal reserved instances per account per zone | 20 | |
Instance type restrictions | gn6i and t5 instance families do not support regional reserved instances, splitting, or merging. Available instance types are shown on the purchase page. | Not applicable |
Resources that can be offset | Only pay-as-you-go instances (not spot instances) are eligible. Only computing resource costs (vCPUs and memory) can be offset; network and storage costs cannot. Windows-type reserved instances also offset image costs. See Billing overview. | Not applicable |
For more information, see What is a reserved instance?
Savings plans
Restriction item | Limit | How to increase quota |
Maximum savings plans per account | 200 | Not applicable |
Resources that can be offset | Only pay-as-you-go ECS and Elastic Container Instances (ECI) (not spot instances) are eligible. For ECS instances, eligible resources include computing resources (vCPUs and memory), images, system disks, data disks (capacity, provisioned performance, and burst performance fees), and fixed public bandwidth. For ECI instances without a specified instance type, only computing resources (vCPUs and memory) can be offset. See Billing overview, ECI instance billing, and Savings plan offset items and rules. | Not applicable |
For more information, see What is a savings plan?
Storage Capacity Units
Restriction item | Limit | How to increase quota |
Maximum capacity per SCU purchase | 50 TiB | |
Maximum SCUs per region | 100 | Not applicable |
Supported products | ESSDs, standard SSDs, ultra disks, and basic disks; Capacity NAS and Performance NAS file systems; standard snapshots; Standard, Infrequent Access (IA), and Archive OSS; Cloud Backup vaults; Photo Album and Cloud Storage. | Not applicable |
Offset type | Only pay-as-you-go bills. Pay-as-you-go bills for spot instance disks cannot be offset. | Not applicable |
Effective time | Set at purchase. Cannot be more than six months after the creation time. | Not applicable |
Manage SCUs via API | Not supported. | Not applicable |
For more information, see Storage Capacity Units.
Launch templates
Restriction item | Limit | How to increase quota |
Maximum launch templates per account per region | Quota ID: | |
Maximum versions per launch template | Quota ID: | |
Template parameters | All parameters are optional when creating a template. Parameters required for instance creation (such as instance type and image) must be provided when using the template. | Not applicable |
Modifying a launch template | Existing templates cannot be modified. Create a new version to update configuration. See Manage launch template versions. | Not applicable |
For more information, see Launch template overview.
Deployment sets
Restriction item | Limit | How to increase quota |
Maximum deployment sets per account per region | Quota ID: | |
Instances per deployment set | Depends on the deployment strategy. See Deployment strategies. | Not applicable |
Dedicated hosts in a deployment set | Not supported. | Not applicable |
Region and zone requirements | An instance and its deployment set must be in the same region. For low-latency network strategy, all instances must be in the same zone. | Not applicable |
Supported instance types | Supported instance families vary by deployment strategy. Call DescribeDeploymentSetSupportedInstanceTypeFamily with a deployment strategy to get the supported families. | Not applicable |
Merge deployment sets | Not supported. | Not applicable |
For more information, see Deployment sets.
Auto provisioning groups
Restriction item | Limit | How to increase quota |
Provision instances across regions | Not supported. | Not applicable |
Configuration sources per group | One launch template version as the base configuration. Instance types in the template can be extended to form multiple resource pools. | Not applicable |
Maximum resource pools per group | 20 (zone and instance type combinations) | Not applicable |
Maximum instances per group | 1,000 | Not applicable |
For more information, see Auto provisioning group overview.
Cloud Assistant
Restriction item | Limit | How to increase quota |
Maximum commands per account per region | Quota ID: | |
Task output size per account per region | Quota ID: | Not applicable |
Task output retention period per account per region | Quota ID: | Not applicable |
Maximum activation codes for managed instances per account per region | Quota ID: | Not applicable |
Maximum instances per command execution per account per region | Quota ID: | |
Script size limits (Base64-encoded Bat, PowerShell, or Shell scripts) | Create command: 18 KB. Run and save command: 18 KB. Run command without saving: 24 KB. Upload file: 32 KB. | Not applicable |
Maximum custom parameters per command | 20 | Not applicable |
Supported operating systems | Alibaba Cloud Linux; CentOS 6, 7, 8, and later; CoreOS; Debian 8, 9, 10, and later; OpenSUSE; Red Hat Enterprise Linux 5, 6, 7, and later (requires manual RPM installation, see Install the Cloud Assistant Agent); SUSE Linux Enterprise Server 11, 12, 15, and later; Ubuntu 12, 14, 16, 18, and later; FreeBSD 11, 12, 13, 14, and later; Windows Server 2012, 2016, 2019, and later. The Cloud Assistant Agent is pre-installed on instances created from ECS public images. For custom images or Alibaba Cloud Marketplace images, verify OS support and install the agent manually. | Not applicable |
For more information, see Cloud Assistant overview.
Network connectivity diagnosis
Restriction item | Limit | How to increase quota |
Maximum diagnostic lines per region | 100 | Not applicable |
Maximum diagnostic tasks per region | 1,000 | Not applicable |
Maximum concurrent diagnostic tasks per region | 5 | Not applicable |
For more information, see Diagnose network connectivity.
API rate limits
Restriction item | Limit | How to increase quota |
ECS API rate limit (version 2014-05-26) | Applies to APIs for resources such as images, security groups, and block storage. See View the ECS API rate limit. | Cannot be increased |
Elastic Block Storage API rate limit (version 2021-07-30) | Applies to advanced block storage feature APIs. See View or increase the Elastic Block Storage API rate limit. |
For more information, see Integration overview.