Modify the configuration and billing method of a pay-as-you-go CLB instance - Server Load Balancer

Modify the configuration or billing method of a pay-as-you-go CLB instance.

Note

As of 00:00:00 on June 1, 2025 (UTC+8), you can no longer create new pay-by-specification CLB instances or switch instances from pay-by-usage to pay-by-specification. For more information, see End of sale for pay-by-specification CLB instances.

Pay-as-you-go billing methods

The pay-as-you-go model includes two instance billing methods: pay-by-usage and pay-by-specification (discontinued). The following table shows their relationship.

Instance billing method	Instance type	Public network billing method
pay-by-usage	public network	pay-by-data-transfer
pay-by-usage	private network	Not applicable
pay-by-specification (discontinued)	public network	pay-by-data-transfer
	public network	pay-by-bandwidth
	private network	Not applicable

Switch from pay-by-specification to pay-by-usage

Switching from pay-by-specification to pay-by-usage does not interrupt services.

Rules

Pay-by-usage instances require no specification. A single instance supports up to 1,000,000 concurrent connections, 100,000 CPS, 50,000 QPS, and 5 Gbps bandwidth.
Note
- Switching from pay-by-specification to pay-by-usage may degrade performance for Super I or higher specifications. Proceed with caution.
- By default, CLB specifications above Super I are unavailable. For Layer 4 workloads requiring more concurrent connections, use NLB. For Layer 7 workloads requiring higher QPS, use ALB.
  - What is Network Load Balancer (NLB)?
  - What is Application Load Balancer (ALB)?
Billing data in the Billing Management console may take one to two hours to update.

Effective time

The change takes effect immediately if the public network billing method stays the same. If you also change the public network billing method (for example, from pay-by-bandwidth to pay-by-data-transfer), all changes take effect at 00:00:00 the next day. Before the changes take effect, you cannot modify other configurations.

Instance type	Before change		After change		Effective time
public network	pay-by-specification	pay-by-bandwidth	pay-by-usage	pay-by-data-transfer	Takes effect at 00:00:00 the next day
public network	pay-by-specification	pay-by-data-transfer	pay-by-usage	pay-by-data-transfer	Effective immediately
private network	pay-by-specification	Not applicable	pay-by-usage	Not applicable	Effective immediately

Billing impact

After switching to pay-by-usage, you no longer specify an instance specification. LCU fees are charged based on actual usage, as described in Pay-as-you-go.

Scenarios

Suitable for periodic or highly fluctuating traffic.

Procedure

Log on to the CLB console.
Select the region where the instance is deployed.
On the Instances page, find the instance you want to manage and choose > Modify Configuration in the Actions column.
On the Upgrade/Downgrade page, set Instance Billing Method to Pay-by-usage.
Read and select the terms of service, click Create Now, and then complete the payment.
You can view the new billing method of the instance on the Instance Details tab.

Scale a pay-by-specification instance

Item	Description
Modification rules	You can modify the specification, public network billing method, and bandwidth of a pay-by-specification instance.
Effective time	Changes take effect immediately if the public network billing method stays the same. If you also change the billing method (for example, from pay-by-bandwidth to pay-by-data-transfer), all changes take effect at 00:00:00 the next day. Note If you change both the specification and the public network billing method, all changes take effect at 00:00:00 the next day.
Billing impact	After modification, billing follows the new settings, as described in Pay-as-you-go.
Scenarios	Scale the instance when the current specification, bandwidth, or billing method no longer meets your needs.

Log on to the CLB console.
Select the region where the instance is deployed.
On the Instances page, find the instance you want to manage and choose > Modify Configuration in the Actions column.

On the Upgrade/Downgrade page, configure the following parameters.

Parameter	Description
Instance Billing Method	Valid values: Pay-by-specification and Pay-by-usage. To scale a pay-by-specification instance, select Pay-by-specification.
Load Balancer Specification	Select an instance specification. Each specification provides different performance metrics, as described in Instance types.
SLB Instance	Displays the current instance type. This value cannot be changed.
Public Network Billing Method	Select a billing method for the public network connection. Pay-by-data-transfer: Charges based on data transfer. Pay-by-bandwidth: Charges based on a fixed bandwidth. Note For private network instances, only pay-by-data-transfer is displayed. No data transfer fees apply.
Peak Bandwidth	Select a bandwidth value. Available only when Public Network Billing Method is set to Pay-by-bandwidth.
Listener settings	Set a peak bandwidth for each listener. The value must be a positive integer, and the total bandwidth of all listeners cannot exceed the instance bandwidth. Available only when Public Network Billing Method is set to Pay-by-bandwidth.

Read and select the terms of service, click Create Now, and then complete the payment.
You can view the updated instance specification, public network billing method, or bandwidth on the Instance Details tab.

FAQ

Switching from performance-shared to performance-guaranteed instances

CLB instances are either performance-guaranteed or performance-shared. Performance-shared instances can no longer be created.
Switching from performance-shared to performance-guaranteed is irreversible.
This switch does not affect services or change the instance IP address. Perform the switch during off-peak hours, or use DNS to balance load across instances beforehand.

Server Load Balancer:Modify the configuration of pay-as-you-go instances