Limits
GPU-accelerated instances run on Elastic Compute Service (ECS), so they share all ECS limits and quotas. This topic lists those limits and explains how to adjust adjustable quotas.
General limits
The following restrictions apply to all ECS instances, including GPU-accelerated instances:
Only ECS Bare Metal Instance families and Super Computing Cluster (SCC) instance families support secondary virtualization. Other instance families do not support installing virtualization software or secondary virtualization.
ECS does not support sound card applications.
External hardware devices — such as hardware dongles, USB flash drives, external hard disks, and bank U keys — cannot be attached directly to ECS instances. Use software-based verification methods instead, such as software dongles or two-factor authentication with one-time passwords.
ECS does not support multicast protocols. Use unicast protocols instead.
Simple Log Service does not support 32-bit Linux ECS instances. For a list of supported instance types, see Install Logtail on a Linux server and Install Logtail on a Windows server.
Before applying for Internet Content Provider (ICP) filings for websites hosted on ECS instances, make sure your instances meet ICP filing requirements. Each ECS instance has a limited number of ICP filing service identification numbers. For details, see Check the instance for ICP filing and access information.
Some software or application licenses are tied to instance hardware. Migrating data to a different instance may change the hardware fingerprint and invalidate those licenses.
How to view and adjust quotas
Most quotas in this topic are managed in the Quota Center console. To check a current quota value or request an increase:
Go to the Quota Center console.
In the navigation pane, select the ECS product.
Find the quota item by name. The current value and adjustability are shown in the table.
If the quota is adjustable, click Apply and enter the new value you need.
For quotas marked Submit a ticket, the Quota Center does not support self-service adjustment — open a support ticket instead.
Instance limits
| Item | Limit | Adjustable |
|---|---|---|
| Create ECS instances in the Chinese mainland | Real-name verification required | N/A |
| Instance quota (by region, zone, instance type, billing method, and network type) | Varies by instance type | Quota Center |
| Max subscription instances purchased at one time | See Quota Center | Quota Center |
| Max launch templates per account | See Quota Center | Quota Center |
| Max versions per launch template | See Quota Center | Quota Center |
| Change billing method: pay-as-you-go to subscription | Not allowed for retired instance types. See Retired instance types. | N/A |
| Change billing method: subscription to pay-as-you-go | Eligibility depends on your ECS usage history. A refund may apply, subject to a monthly refund cap. Review the refund details on the Switch to Pay-as-you-go page in the ECS console. | N/A |
Reserved instance limits
| Item | Limit | Adjustable |
|---|---|---|
| Max regional reserved instances per account | 20 | Submit a ticket |
| Max zonal reserved instances per zone per account | 20 | Submit a ticket |
| Supported instance families | General-purpose: g7, g7a, g6e, g6, g5, g5ne, sn2ne; Compute-optimized: c7, c7a, c6e, c6, c5, ic5, sn1ne; Memory-optimized: r7, r7a, r6e, r6, r5, re6, re4, se1ne; Big data: d2s; Local SSD: i3, i3g, i2, i2g, i2gne; High clock speed: hfg7, hfc7, hfr7, hfg6, hfc6, hfr6, hfg5, hfc5; GPU-accelerated compute-optimized: gn7, gn6i, gn6e, gn6v, gn5, gn5i; ECS Bare Metal Instance: ebmgn7, ebmgn6i, ebmgn6e, ebmg6, ebmc6, ebmr6, ebmhfg6, ebmhfc6, ebmhfr6; Burstable: t6, t5 | N/A |
For the full list of reserved instance constraints, see the Limits section in the reserved instances overview.
Savings plan limits
| Item | Limit | Adjustable |
|---|---|---|
| Max savings plans per account | 40 | N/A |
| Unsupported instance types | Retired instance types: t1, s1, s2, s3, m1, m2, c1, c2 | N/A |
For more information, see What is a savings plan?
Block storage limits
| Item | Limit | Adjustable |
|---|---|---|
| Create pay-as-you-go disks in the Chinese mainland | Real-name verification required | N/A |
| System disks per instance | 1 | N/A |
| Data disks per instance | Up to 64 (varies by instance type). At instance creation, you can attach 1 system disk and up to 16 data disks. Attach additional data disks after the instance is created. To check the limit for a specific instance type, call DescribeInstanceTypes. For general limits by instance family, see Overview of instance families. | N/A |
| Capacity of all disks | Varies by disk category | Quota Center |
| Capacity: basic disk | 5 GiB–2,000 GiB | N/A |
| Capacity: standard SSD | 20 GiB–32,768 GiB | N/A |
| Capacity: ultra disk | 20 GiB–32,768 GiB | N/A |
| Capacity: Enterprise SSD (ESSD) | PL0: 1 GiB–65,536 GiB; PL1: 20 GiB–65,536 GiB; PL2: 461 GiB–65,536 GiB; PL3: 1,261 GiB–65,536 GiB | N/A |
| Capacity: ESSD AutoPL disk | 1 GiB–65,536 GiB | N/A |
| Capacity: ESSD Entry disk | 10 GiB–32,768 GiB | N/A |
| Capacity: local SSD (single disk) | 5 GiB–800 GiB | N/A |
| Capacity: all local SSDs on a single instance | 1,024 GiB | N/A |
| Capacity: system disk | Windows Server: 40 GiB–2,048 GiB; FreeBSD: 30 GiB–2,048 GiB; Other Linux distributions: 20 GiB–2,048 GiB. Basic disks used as system disks are capped at 500 GiB. | N/A |
| Attach new local disks to an instance that already has local disks | Not supported | N/A |
| Change configurations of instances with local disks | Only bandwidth configurations can be changed | N/A |
| System disk mount point (Linux) | /dev/vda | N/A |
| Data disk mount points (Linux) | 1st–25th disk: /dev/xvd[b-z]; 26th disk onward: /dev/xvd[aa-zz] (for example, the 26th disk is /dev/xvdaa, the 27th is /dev/xvdab) | N/A |
Block storage capacity is measured in binary units. 1 GiB = 1,024 MiB.
SCU limits
Storage capacity units (SCUs) let you pre-pay for storage and apply the credits across multiple resource types.
| Item | Limit | Adjustable |
|---|---|---|
| Max capacity per SCU | 50 TiB | Submit a ticket |
| Max SCUs per region | 100 | N/A |
| Resource types that support SCUs | ESSDs, standard SSDs, ultra disks, and basic disks; File Storage NAS Capacity and NAS Performance; standard snapshots; Object Storage Service (OSS) Standard, Infrequent Access, and Archive storage classes; Cloud Backup storage capacity; Photo and Drive Service (PDS) | N/A |
Snapshot limits
| Item | Limit | Adjustable |
|---|---|---|
| Max manual snapshots per disk | 256 | N/A |
| Max automatic snapshots per disk | 1,000 | N/A |
| Max automatic snapshot policies per region per account | 100 | N/A |
Image limits
| Item | Limit | Adjustable |
|---|---|---|
| Max custom images per account | See Quota Center | Quota Center |
| Max users to share a single image with | See Quota Center | Quota Center |
| 32-bit image support | Instance types with 4 GiB or more of memory do not support 32-bit images | N/A |
SSH key pair limits
| Item | Limit | Adjustable |
|---|---|---|
| Max SSH key pairs per region per account | 500 | N/A |
| Supported OS | Linux images only | N/A |
Public bandwidth limits
From November 27, 2020, the maximum bandwidth available to create ECS instances or change the configurations of ECS instances is subject to the throttling policy for your account. To increase these caps, submit a ticket. The following regional aggregate bandwidth caps apply:
Pay-by-traffic: The total bandwidth of all instances in a single region cannot exceed 5 Gbit/s.
Pay-by-bandwidth: The total bandwidth of all instances in a single region cannot exceed 50 Gbit/s.
| Item | Limit | Adjustable |
|---|---|---|
| Max inbound bandwidth per instance | If purchased outbound bandwidth is 10 Mbit/s or less: 10 Mbit/s. If purchased outbound bandwidth exceeds 10 Mbit/s: equal to the purchased outbound bandwidth. | N/A |
| Max outbound bandwidth per instance (pay-by-traffic) | Subscription instance: 200 Mbit/s; Pay-as-you-go instance: 100 Mbit/s | N/A |
| Max outbound bandwidth per instance (pay-by-bandwidth) | 200 Mbit/s | N/A |
| Change public IP address | Within 6 hours after instance creation; up to 3 times total | N/A |
Outbound bandwidth is also subject to the network baseline bandwidth and network burst bandwidth of the instance type. For details, see Overview of instance families.
When using pay-by-traffic, the bandwidth values are upper limits, not guaranteed throughput. Under high demand, actual bandwidth may be lower. Use pay-by-bandwidth if your workload requires guaranteed bandwidth.
Security group limits
| Item | Basic security groups | Advanced security groups |
|---|---|---|
| Max security groups per account | See Quota Center | Same as basic |
| Max classic network instances per security group | 1,000. If more than 1,000 classic network instances need internal network access to each other, distribute them across multiple security groups and allow cross-group access. | Not supported |
| Max Virtual Private Cloud (VPC) instances per security group | Determined by the private IP address quota for the security group | No limit |
| Max security groups per ECS instance | 5 (can be changed to 4 or 10 by submitting a ticket) | Same as basic |
| Max security groups to which an elastic network interface (ENI) of an ECS instance can belong | Same as basic | |
| Max inbound and outbound rules per security group | 200. The product of (security groups per instance) x (rules per security group) cannot exceed 1,000. For example: 4 groups x 250 rules = 1,000; 5 groups x 200 rules = 1,000; 10 groups x 100 rules = 1,000. If a prefix list is referenced in a rule, its maximum entry count counts toward the rule quota regardless of how many entries currently exist. | Same as basic |
| Max total rules across all security groups per elastic network interface (ENI) | 1,000 | Same as basic |
| Max rules that reference security groups as authorization objects | 20 | 0 (not allowed) |
| Max private IP addresses per VPC security group | 6,000. If more than 6,000 instances need mutual internal network access, distribute them across multiple security groups and allow cross-group access. See also: Quota Center. | 65,536 |
| Port 25 (outbound) | Disabled by default. Use port 465 (SSL) for sending email instead. | Same as basic |
Prefix list limits
| Item | Limit | Adjustable |
|---|---|---|
| Max prefix lists per region per account | 100 | N/A |
| Max entries per prefix list | 200 | N/A |
| Max resources associated with a prefix list | 1,000 | N/A |
Network connectivity diagnostics limits
| Item | Limit | Adjustable |
|---|---|---|
| Max diagnostic paths per region | 100 | N/A |
| Max diagnostic tasks per region | 1,000 | N/A |
| Max concurrent diagnostic tasks per region | 5 | N/A |
Deployment set limits
| Item | Limit | Adjustable |
|---|---|---|
| Max deployment sets per account | See Quota Center | Quota Center |
| Max instances per deployment set | See Deployment set | N/A |
| Supported instance types | Call DescribeDeploymentSetSupportedInstanceTypeFamily to get supported instance families by deployment strategy | N/A |
Cloud Assistant limits
| Item | Limit | Adjustable |
|---|---|---|
| Max Cloud Assistant commands per account | See Quota Center | Quota Center |
| Output size of a Cloud Assistant command execution task | ||
| Retention period of a Cloud Assistant command execution record | ||
| Max activation codes for registering Cloud Assistant managed instances | ||
| Max instances on which a command can be run in an execution |
ENI limits
| Item | Limit | Adjustable |
|---|---|---|
| Max secondary ENIs per account | See Quota Center | Quota Center |
Tag limits
For tag limits, see the Limits section in the tag overview.
API limits
| Item | Limit | Adjustable |
|---|---|---|
| ECS API rate limits | See the API Rate Limits page for ECS in the Quota Center console | N/A |
For Virtual Private Cloud (VPC) limits, see Limits and quotas.