I'm using Nginx upsteam to 4 servers. This is my configuration.

update api_sever {
server server1:8080 weight=1;
server server2:8080 weight=1;
server server3:8080 weight=1;
server server4:8080 weight=1;
}
And I counting upstream_addr each server.

grep -c "10.111.1.1(server1 IP)") server.access.log

If I counting on server 1, sever1 upstream_addr count is double then other servers. when i counting on server 2 It's same result(server2 upstream_addr count is twice)

Why? someone help me!

Without specifying a balance method such as 'hash'/'leastconn' a server which has the best response time is chosen more often then those who's response time are higher.

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nginx for Windows http://nginx-win.ecsds.eu/

http://nginx.org/en/docs/http/load_balancing.html

In this document, round-robin is defaults.
Can I find other documents?