nginx error : worker_connections are not enough

Question

I'm a new to Nginx.

What i want to do with Nginx is Traffic load balancing. To do it, i configured nginx.conf like below

system structure

      udp        udp
    A <--> Nginx <--> Backend 1
                 <--> Backend 2

nginx.conf

user  nginx;
worker_processes  4;
worker_rlimit_nofile 30000;

error_log  /var/log/nginx/error.log warn;
pid        /var/run/nginx.pid;

stream {
upstream udp_upstreams {
   server 1:1:1:1:9997 fail_timeout=60s;
   server 1:1:1:2:9997 fail_timeout=60s;
}

server {
    listen 9000 udp;
    proxy_pass udp_upstreams;
    proxy_timeout 3s;
    proxy_responses 1;
    error_log /var/log/nginx/udp.log;
}
}

events {
    worker_connections  10240;
}

when i run nginx, nginx prints a lot of below message.

2016/04/27 04:50:36 [alert] 3137#3137: *446352 10240 worker_connections are not enough while connecting to upstream, udp client: 3.3.3.3, server: 0.0.0.0:9000, upstream: "1.1.1.2:9997", bytes from/to client:0/0, bytes from/to upstream:0/0
2016/04/27 04:50:36 [alert] 3136#3136: *446353 10240 worker_connections are not enough while connecting to upstream, udp client: 3.3.3.3, server: 0.0.0.0:9000, upstream: "1.1.1.1:9997", bytes from/to client:0/0, bytes from/to upstream:0/0

How do i configure nginx.conf to solve it? I have already set the work_connections value to 40000. But it was useless.

Thanks in advance.

Answer 1

I just ran into the same problem and found a solution after I stopped wild googling and started to read the nginx documentation. ^_^;

The parameter 'proxy_responses' tells nginx to wait for x responses to the request. I my case, log forwarding, there is non. So nginx waits for and failes the server.

Solution:

proxy_responses 0

Docs: http://nginx.org/en/docs/stream/ngx_stream_proxy_module.html#proxy_responses