Hi,

We are using NGINX as Load Balancer for load balancing RADIUS UDP traffic.

It seems NGINX is not retrying to send messages to another upstream server if one of the upstream servers is down.

We are using NGINX 1.16.1. But the same behaviour exists in all NGINX version upto NGINX 1.19.

In older NGINX version (1.13.10/1.14.1) this retry is working fine without any issues.

Following is our NGINX configuration -

server {
listen 1813 udp reuseport;

proxy_pass udp_radius;
proxy_connect_timeout 60s;
proxy_timeout 5s;
proxy_responses 1;
proxy_requests 1;

proxy_buffer_size 64k;

#access_log /var/log/nginx/radius.log upstreamlog buffer=64k flush=1m;
access_log off;
}