This topic lists the resource quotas of Server Load Balancer (SLB).

SLB provides an API to query the default limits of an SLB instance.

Resource Default limit
Limits on SLB instances
The number of SLB instances per account 30
The number of times that an ECS instance can be added to SLB instances 50
The number of backend servers that can be added to an SLB instance 200
The number of listeners that can be added to an SLB instance 50
The number of domain name-based and URL-based forwarding rules that can be added to a Layer-7 listener 40
The number of domain name extensions that an HTTPS listener can create 3
The frequency of API calls per AccessKey 5,000 times/day
The frontend and backend port range used by a listener (public cloud) 1-65535
The frontend and backend port range used by a listener (Ant Financial Cloud) 80, 443, 2800-3300, 5000-10000, 13000-14000
Limits on certificates
The number of server certificates that can be uploaded in a region 100
The number of CA certificates that can be uploaded in a region 100
Limits on access control lists
The number of access control lists that can be created in a region 50
The number of IP entries that can be added to an access control list 300
The number of IP entries that can be added to an access control list in an API call 50
The number of times that an access control list can be added to listeners 50