This document describes how to configure health check for the Non-Web Service in Anti-DDoS Pro.
Follow these steps to configure health check rules for the Non-Web Service in the Anti-DDoS Pro console.
Log on to the Alibaba Cloud Security Anti-DDoS console, and go to Anti-DDoS Pro > Non-Web Service.
Select the target Anti-DDoS instance and IP.
Locate the corresponding Forwarding protocol/port, and click Configure under the Health Check column of the target protocol/port to configure health check.
- Health check is disabled by default.
- If the forwarding protocol is TCP, you can select either TCP or HTTP as the health check method.
We recommend that you use the default values for health check configuration.
|Port||Test port used by the health check service to access backend servers. The default port is the backend port specified in the listener configuration.|
|Response Timeout||Maximum timeout value for each health check response. If the backend server fails to respond correctly within the specified time period, the health check fails.|
|Check Interval||Interval between health checks. |
All nodes within the Anti-DDoS Pro cluster perform health check on backend servers independently and in parallel based on this attribute. From individual statistics on a backend server, you may find that health-check requests sent from Anti-DDoS Pro do not strictly follow the specified time interval, because health-checks for different Anti-DDoS Pro nodes are not performed synchronously.
|Unhealthy Threshold||This attribute specifies the number of consecutive health check failures allowed before a health check status is considered as unhealthy.|
|Healthy Threshold||This attribute specifies the number of consecutive successful health check requests necessary for a health check status be considered as healthy.|
|Domain name and health-check path (only supports HTTP protocol)||By default, layer-7 health check requests are HTTP HEAD requests sent by Anti-DDoS Pro to the default home page configured for the application server. |
|Normal status code||The normal HTTP status code for health check. The default value is http_2xx, and cannot be changed. If the HTTP returns a non-2xx status code, then the server is considered as unhealthy by default.|
|Other parameter options||Same as the parameters for layer-4 health check.|
For more information about the principles of health check, see Health check overview.