If the public bandwidth that you use for a Server Load Balancer (SLB) instance in the stress testing is a fixed bandwidth, no traffic charges are incurred. If the public bandwidth supports the pay-as-you-go billing method, you are charged based on the existing traffic billing policies configured for SLB instances.
Traffic fees for the public IP addresses of SLB instances follow the following rules:
If the public bandwidth of an ECS instance is a fixed bandwidth, no traffic fee is incurred because the traffic fee is paid when the SLB instance is purchased.
If the public bandwidth supports the pay-as-you-go billing method, you are charged based on the existing traffic billing policies configured for SLB instances. If you do not want to perform the stress testing over the Internet, we recommend that you use the private IP address of the SLB instance or the internal IP address of the Elastic Compute Service (ECS) instance associated with the SLB instance in the test script.