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Server Load Balancer:Quotas and limits

Last Updated:Mar 23, 2026

This topic explains the quotas and limits for Application Load Balancer (ALB) and how to manage them.

Limitations

The following limits are fixed and cannot be increased.

Listener limits

Resource

Edition

Default limit

Number of Access Control Lists (ACLs) per listener

Basic/Standard/WAF-Enabled

3

Number of ACL entries per listener

Basic

300

Standard/WAF-Enabled

500

Forwarding rule limits

Resource

Edition

Default limit

Number of actions per forwarding rule

Basic

3

Standard/WAF-enabled

5

Number of match conditions per forwarding rule

Basic

5

Standard/WAF-enabled

10

Number of wildcard entries per forwarding rule

Basic

5

Standard/WAF-enabled

10

Server group limits

Resource

Edition

Default limit

Number of backend servers (IP addresses and ports) per server group

Basic/Standard/WAF-enabled

1,000

ACL and security policy limits

Resource

Edition

Default limit

Number of associated listeners per ACL

Basic/Standard/WAF-enabled

50

Number of ACL entries per ACL

Basic/Standard/WAF-enabled

500

Number of associated listeners per custom security policy

Basic/Standard/WAF-enabled

10

Number of ACL entries per ALB instance

Basic/Standard/WAF-enabled

800

Regional limits

Resource

Edition

Default limit

Number of custom security policies per region

Basic/Standard/WAF-enabled

50

Number of health check templates per region

Basic/Standard/WAF-enabled

50

Number of ACLs per region

Basic/Standard/WAF-enabled

1,000

Number of server groups per region

Basic/Standard/WAF-enabled

3,000

Other limits

The following limits apply only to upgraded ALB Instances. Pre-upgrade ALB Instances are not affected.

Within a single Availability Zone, an ALB Instance supports a maximum of 250,000 Concurrent Connections to a single Backend Server or IP address. If this limit is exceeded, Port allocation may fail, affecting new connections.

  • To ensure this elastic capability:

    • Reserve at least 8 IP addresses in each vSwitch where the ALB instance is located, and allow the CIDR blocks of these vSwitches in advance.

    • Ensure that the Security Group rule Quota for your ECS Instances or Elastic Network Interfaces (ENIs) is sufficient to accommodate the rules required by the ALB-managed Security Group.

      The ALB-managed Security Group automatically allows traffic from local IP addresses by using rules with a priority of 1. The total number of rules must not exceed the Quota: Number of ALB-managed Security Group rules + Number of custom Security Group rules associated with the ALB instance ≤ Security Group rule quota for an ECS Instance or ENI. For more information, see ALB Security Group limits.

  • To avoid exceeding the Concurrent Connection limit, add more Backend Servers or IP addresses to the Server Group. Adding more servers distributes connection requests and reduces the load on any single server.

General quotas

  • If a resource is associated multiple times within the same scope, its quota usage is calculated cumulatively. For example, if the same Backend Server is associated with multiple Listeners and Forwarding Rules of an ALB Instance, it counts multiple times toward the quota for the number of Backend Servers per ALB Instance.

  • The default quota values in this topic are for reference only. For actual values, refer to the Console.

Instance quotas

Quota name

Description

Default

Adjustable up to

Adjustable

alb_quota_loadbalancers_num

Number of ALB Instances per Alibaba Cloud Account per Region.

60

150

Yes

Basic edition ALB Instance quotas

Quota name

Description

Default

Adjustable up to

Adjustable

alb_quota_loadbalancer_certificates_num_basic_edition

Number of Additional Certificates per ALB Instance (not including the default Certificate).

10

150

Yes

alb_quota_loadbalancer_rules_num_basic_edition

Number of Forwarding Rules per ALB Instance (not including the default rule).

40

100

Yes

alb_quota_loadbalancer_servers_num_basic_edition

Number of Backend Servers per ALB Instance.

200

400

Yes

alb_quota_loadbalancer_listeners_num_basic_edition

Number of Listeners per ALB Instance.

50

80

Yes

Standard edition ALB Instance quotas

Quota name

Description

Default

Adjustable up to

Adjustable

alb_quota_loadbalancer_certificates_num_standard_edition

Number of Additional Certificates per ALB Instance (not including the default Certificate).

25

300

Yes

alb_quota_loadbalancer_rules_num_standard_edition

Number of Forwarding Rules per ALB Instance (not including the default rule).

100

200

Yes

alb_quota_loadbalancer_servers_num_standard_edition

Number of Backend Servers per ALB Instance.

1,000

1,500

Yes

alb_quota_loadbalancer_listeners_num_standard_edition

Number of Listeners per ALB Instance.

50

100

Yes

WAF-enabled ALB Instance quotas

Quota name

Description

Default

Adjustable up to

Adjustable

alb_quota_loadbalancer_certificates_num_standardwithwaf_edition

Number of Additional Certificates per ALB Instance (not including the default Certificate).

25

300

Yes

alb_quota_loadbalancer_rules_num_standardwithwaf_edition

Number of Forwarding Rules per ALB Instance (not including the default rule).

100

200

Yes

alb_quota_loadbalancer_servers_num_standardwithwaf_edition

Number of Backend Servers per ALB Instance.

1,000

1,500

Yes

alb_quota_loadbalancer_listeners_num_standardwithwaf_edition

Number of Listeners per ALB Instance.

50

100

Yes

Listener quotas

Quota name

Description

Default

Adjustable up to

Adjustable

alb_quota_max_request_timeout

Maximum request timeout for a Listener.

600 seconds

3,600 seconds

Yes

alb_quota_max_idle_timeout

Maximum idle timeout for a Listener.

600 seconds

3,600 seconds

Yes

Only instances upgraded as described in the Application Load Balancer (ALB) Instance Upgrade Announcement support increasing the alb_quota_max_request_timeout and alb_quota_max_idle_timeout quotas to a maximum of 3600 seconds. For non-upgraded instances, the maximum for these quotas is 900 seconds.

Server Group quotas

Quota name

Description

Default

Adjustable up to

Adjustable

alb_quota_server_added_num

The number of Server Groups that a single Backend Server (by IP address) can be added to.

200

300

Yes

alb_quota_servergroup_attached_num

Number of times a single Server Group can be associated with Listeners and Forwarding Rules.

50

100

Yes

alb_quota_server_groups_weight

Maximum weight for a single Server Group as a target of a Forwarding Rule.

100

10,000

Contact Sales

Reserved capacity quotas

Quota name

Description

Default

Adjustable up to

Adjustable

alb_quota_reserved_capacity_units_per_loadbalancer

Maximum reserved Load Balancer Capacity Units (LCUs) per ALB Instance.

5,000

-

Contact Sales

alb_quota_reserved_capacity_units_per_region

Maximum reserved LCUs per Region.

20,000

-

Contact Sales

API rate quotas

You can view the rate quotas for Application Load Balancer (ALB) in Quota Center.

Privilege quotas

Privilege quotas apply to features that require authorization from Alibaba Cloud. By default, these features are unavailable until access is granted.

Quota ID

Description

Application portal

slb_user_visible_gray_label/ip_target_cidr_not_limited

Unrestricted CIDR blocks for IP-based Server Groups

Apply

slb_user_visible_gray_label/alb_extensible_edition

Extended Edition for Application Load Balancer (ALB)

Apply

slb_user_visible_gray_label/alb_resource_reservation

Resource reservation for Application Load Balancer (ALB)

Apply

slb_user_visible_gray_label/support_sm_certificate

Support for SM certificates on Application Load Balancer (ALB)

Apply

Manage quotas

You can manage Application Load Balancer (ALB) quotas in one of the following ways:

  • Quota Center: Use this method if you need to manage quotas for multiple Alibaba Cloud services from a central location.

  • Quota Center page in the Load Balancer Console: Use this method if you only need to manage quotas for ALB.

View quotas

Quota Center

  1. Log in to the Quota Center console. In the left-side navigation pane, click Product List and select a quota type: General Quotas, API Rate Limits, or Privileges.

  2. On the Product List page, go to the Networking section and click Application Load Balancer (ALB) to view its quotas.

Load Balancer Console

  1. Log in to the Quota Center page in the Load Balancer Console and select Application Load Balancer (ALB) as the product.

  2. Select a quota type (General Quota, API Rate Limit, or Privilege) to view the quota information.

Increase quotas

Quota Center

  1. Log in to the Quota Center console. In the left-side navigation pane, click Product List, select a quota type (General Quotas or Privileges), and then click Application Load Balancer (ALB) in the Networking section.

  2. Find the quota that you want to increase and click Apply in the Actions column.

  3. In the dialog box, enter the required information and click OK.

    The Technical Support team for each cloud service reviews quota increase requests. Provide a reasonable value and a detailed justification for your request. You will be notified of the approval status by SMS and email.

Load Balancer Console

  1. Log in to the Quota Center page in the Load Balancer Console and select Application Load Balancer (ALB) as the product.

  2. Select a quota type (General Quota or Privilege), find the quota that you want to increase, and click Apply in the Actions column.

  3. In the dialog box, enter the required information and click OK.

    The Technical Support team for each cloud service reviews quota increase requests. Provide a reasonable value and a detailed justification for your request. You will be notified of the approval status by SMS and email.

Create quota alerts

You can create alerts for some General Quotas of Application Load Balancer (ALB). When your resource usage reaches a specified threshold, the system sends an alert. This lets you request a quota increase before you reach the limit.

ALB quotas that support alerts

Category

Quota parameter

Description

Additional certificates

alb_quota_loadbalancer_certificates_num_basic_edition

Number of additional certificates per Basic ALB instance (default certificate excluded).

alb_quota_loadbalancer_certificates_num_standard_edition

Number of additional certificates per Standard ALB instance (default certificate excluded).

alb_quota_loadbalancer_certificates_num_standardwithwaf_edition

Number of additional certificates per Web Application Firewall (WAF)-enhanced ALB instance (default certificate excluded).

Forwarding rules

alb_quota_loadbalancer_rules_num_basic_edition

Number of forwarding rules per Basic ALB instance (default rule excluded).

alb_quota_loadbalancer_rules_num_standard_edition

Number of forwarding rules per Standard ALB instance (default rule excluded).

alb_quota_loadbalancer_rules_num_standardwithwaf_edition

Number of forwarding rules per WAF-enhanced ALB instance (default rule excluded).

Number of backend servers

alb_quota_loadbalancer_servers_num_basic_edition

Number of servers that can be added to a Basic ALB instance.

alb_quota_loadbalancer_servers_num_standard_edition

Number of servers that can be added to a Standard ALB instance.

alb_quota_loadbalancer_servers_num_standardwithwaf_edition

Number of servers that can be added to a WAF-enhanced ALB instance.

Listeners

alb_quota_loadbalancer_listeners_num_basic_edition

Number of listeners per Basic ALB instance.

alb_quota_loadbalancer_listeners_num_standard_edition

Number of listeners per Standard ALB instance.

alb_quota_loadbalancer_listeners_num_standardwithwaf_edition

Number of listeners per WAF-enhanced ALB instance.

Server groups

alb_quota_servergroup_attached_num

Number of times a server group can be associated with ALB listeners or forwarding rules.

Backend server (IP)

alb_quota_server_added_num

Number of server groups to which a single backend server (by IP address) can be added.

Region

alb_quota_loadbalancers_num

Number of ALB instances per region.

Quota Center

  1. Log in to the Quota Center console. In the left-side navigation pane, click Product List, select General Quotas, and then click Application Load Balancer (ALB) in the Networking section.

  2. Find the quota and click Create Alarm Rule in the Actions column.

  3. On the Create Alarm Rule page, configure the alert parameters and click Confirm. For more information, see Create a general quota alert.

Load Balancer Console

  1. Log in to the Quota Center page in the Load Balancer Console and select Application Load Balancer (ALB) as the product.

  2. Select General Quota as the quota type, find the quota, and click Create Alarm Rule in the Actions column.

  3. On the Create Alarm Rule page, configure the alert parameters and click Confirm. For more information, see Create a general quota alert.

Create quota templates

Before you begin, make sure that:

Quota Center

  1. Log in to the Quota Center console. In the left-side navigation pane, click Product List, select a quota type (General Quotas or Privileges), and then click Application Load Balancer (ALB) in the Networking section.

  2. Find the quota and click Create Quota Template in the Actions column.

  3. In the Create Quota Template dialog box, configure the settings and click OK.

Load Balancer Console

  1. Log in to the Quota Center page in the Load Balancer Console and select Application Load Balancer (ALB) as the product.

  2. Select a quota type (General Quota or Privilege), find the quota, and click Create Quota Template in the Actions column.

  3. In the Create Quota Template dialog box, configure the settings and click OK.