Users can configure health checks to monitor the health of backend ECSs so that the load balancer only sends requests to properly running backend ECSs. When a faulty ECS is restored to normal operation, LB will automatically resume its external or internal services. Heath check supports protocols including TCP, UDP and HTTP.

Description of configuration parameters for heath check:

Health Check Configuration	Descriptions
Health Check	It is enabled by default and can be disabled or enabled.
Health Check Type	Available modes: HTTP, TCP
Interval	It defaults to 5s. Value range: 1~20940
Timeout	It defaults to 2s. Value range: 2-60s
Maximum Retries	It defaults to 2 retries. Value range: 1-10. After the number of health check failures reaches the threshold of retries, it will enter the state of health check failure.
Check Path	HTTP check type option, containing 1~80 characters. URL path check.
HTTP Method	HTTP check type option. Available value: GET, HEAD
HTTP Status Code	HTTP check type option. It defaults to 200.

Elastic Load Balancing

Health Check