Create a Server Pool
A Server Pool is a collection of backend servers responsible for distributing traffic to improve performance, availability, and reliability.
A default Server Pool is created automatically when you create a Load Balancer.
Create a Server Pool
Step 1: Open the Load Balancer detail page by clicking the Load Balancer name.
Step 2: Select the Server pool tab, then click Create server pool.
Step 3: Enter the Server Pool configuration:
- Server pool name: Enter a name.
- Description: Optional description.
- Protocol: Select the connection protocol for backend servers — HTTP, HTTPS, PROXY, PROXYV2, TCP, or UDP.
- Add server: Select virtual machines from the list (within the VPC). For each member:
- Port: The port the member listens on to handle requests.
- Weight: Priority weight for request distribution. Members with higher weights receive more requests.
Advanced settings:
- Algorithm: Select the load balancing algorithm:
- Round Robin: Distributes requests to members in sequence, cycling back to the first when the last is reached.
- Least Connection: Routes requests to the member with the fewest active connections.
- Source IP: Uses a hash of the client and server IP addresses to route requests consistently to the same server. If a session times out or disconnects, the client is still routed to the same server.
- Sticky session: Ensures requests from the same user are always routed to the same server for a period of time, preserving session state. Select App Cookie, HTTP Cookie, or Source IP. Select None to disable. For App Cookie, also enter the Cookie name.
Health check:
Select the health check protocol based on the Server Pool protocol:
| Health Monitor \ Pool | HTTP | HTTPS | PING | SCTP | TCP | TLS-HELLO | UDP-CONNECT |
|---|---|---|---|---|---|---|---|
| HTTP | Y | Y | Y | N | Y | Y | N |
| HTTPS | Y | Y | Y | N | Y | Y | N |
| PROXY | Y | Y | Y | N | Y | Y | N |
| PROXYV2 | Y | Y | Y | N | Y | Y | N |
| SCTP | Y | N | N | Y | Y | N | Y |
| TCP | Y | Y | Y | N | Y | Y | N |
| UDP | Y | N | N | Y | Y | N | Y |
For HTTP/HTTPS health checks, also configure:
- Path: The path to check. Must start with
/. - HTTP method: The method used for health check requests (GET, HEAD, CONNECT, DELETE, etc.).
- Expected Code: The HTTP status code(s) the backend must return to be considered healthy. Can be a single value (e.g.
200), a list (e.g.200, 202), or a range (e.g.200-204).
Advanced selection:
- Max retries down: Consecutive failed health checks before a member is marked unhealthy. Range: 1–10. Default: 3.
- Max retries: Consecutive successful health checks required for a member to be considered healthy. Range: 1–10. Default: 3.
- Delay (s): Time interval between health check requests.
- Timeout (s): Maximum time to wait for a health check response before marking it as failed.
Click Create server pool to create, or Cancel to discard.