Overview

The default rule function is used to configure global flow control rules, including global configuration, service default configuration, and appid default configuration. It can limit traffic from the two dimensions of concurrency and QPS, and supports custom response messages after triggering flow limiting. The default rule functionality is introduced below.

##Default rules

Menu location: Flow Control Management > Default Rules. Click the menu to enter the default rule viewing page, as shown in the figure.

You can view the current global flow control rules on the page. Click the Edit button to enter the editing page, as shown in the figure.

Global configuration

Global configuration controls flow for the entire node. For example, configure the cluster shared concurrency number: 2000=1000 (single machine) * 2. When the number of concurrent requests on a single node exceeds 1000, the current will be limited.

After checking the Enable option, the cluster shared concurrency and cluster shared QPS configuration boxes will automatically appear. Enter the concurrency and QPS and submit to enable global traffic limiting, as shown in the figure.

Service default configuration

The default configuration of the service controls the flow of each service (the front-end service name in the routing configuration) of the entire node. For example, configure the cluster shared concurrency number: 200=100 (single machine) * 2. When the number of concurrent requests for a certain service on a single node exceeds 100, the flow will be limited.

After checking the Enable option, the cluster shared concurrency and cluster shared QPS configuration boxes will automatically appear. Enter the concurrency and QPS and submit to enable global service current limiting, as shown in the figure.

appID default configuration

The default appid configuration controls the flow of each appid of the entire node (the gateway obtains it from the request header of the request. For more details, please see the appID management function introduction). For example, configure the cluster shared concurrency number: 200=100 (single machine)* 2. When the number of concurrent requests for a certain appid of a single node exceeds 100, the current will be limited.

After checking the Enable option, the cluster shared concurrency and cluster shared QPS configuration boxes will automatically appear. Enter the concurrency and QPS and submit to enable global appid current limiting, as shown in the figure.

Customized current limiting response

After configuring the current limiting response ContentType and the current limiting response message, the client will obtain the configured response message when flow control is triggered. The configuration is as shown in the figure.