Backend server overview

Backend servers refer to servers that are bound to a Server Load Balancing (SLB) instance to process requests forwarded by the SLB instance. An SLB listener uses a specific forwarding mode to distribute requests to backend servers to ensure stable and reliable running of applications.

Best practices for backend servers

When you add a backend server, we recommend that you perform the following operations:

• Install and run the same applications on each backend server that you want to bind to an SLB instance.

• Enable session persistence to enable SLB to maintain a TCP connection for a longer period so that multiple requests can use the same TCP connection. This measure can reduce the load on web servers and increase the SLB throughput.

• Make sure that the security groups of the backend servers have inbound rules for SLB listener ports and health check ports. For more information, see Access control on backend servers.

If the SLB backend service is provided by a backend server of Direct Connect, perform the following steps when you create a listener:

1. Select the Direct Connect Gateway instance type for the backend service.
2. Select a Direct Connect gateway to be added, and then enter the IP address and port number of the backend server of Direct Connect.
   Then, the listener will forward traffic to the backend server of Direct Connect.