Server Load Balancer:FAQ about CLB

Health checks

• What do I do if health checks generate a large number of web logs?

• How do I troubleshoot health check exceptions of a Layer 4 (TCP/UDP) listener?

• How do I troubleshoot health check exceptions of a Layer 7 listener (HTTP/HTTPS)?

• Why do health checks fail even if my website can be accessed?

• Why does the "Connection reset by peer" error occur?

Access to Server Load Balancer (SLB) instances

• Why am I unable to access an SLB instance?

• Why does a timeout error occur when I access the service address of an SLB instance?

• Why does a request timeout error occur during stress testing?

• What do I do if backend database failures cause all websites associated with the same listener of SLB to become inaccessible?

• How do I troubleshoot HTTP 500, 502, and 504 errors?

• CLB status codes

Listener configurations

• Why do the style sheets fail to load when I access a website over an HTTPS listener even if I can use an HTTP listener to access the website?

• Why does an HTTP request to a Layer 7 SLB instance contain the "Transfer-Encoding: chunked" header?

• Why are response headers removed after I use a Layer 7 SLB instance to forward requests?

• What do I do if the "The DomainExtension is related with rules" error occurs when I delete an additional domain name from an SLB instance?

• What do I do if a listener is inaccessible after I use special characters to configure a URL-based forwarding rule?

Backend servers

• Why are requests unevenly distributed among backend servers?

• How do I troubleshoot backend server exceptions?

• How do I remove ECS instances from server groups of SLB?

• Why do backend ECS instances frequently receive requests whose User-Agent value is KeepAliveClient?

• What do I do if a large number of connections to backend servers are in the TIME_WAIT state?

• How do request packets interact with Layer 4 and Layer 7 listeners of SLB?

Session persistence

• What do I do if the session persistence feature does not take effect?

• How do I configure cookies after I enable session persistence and select Rewrite Cookie as the method to handle cookies?

• How do I run the curl command to verify session persistence?