upstream rr_backend {
server 127.0.0.1:8080 weight=5 max_fails=3 fail_timeout=60s;
server 10.9.0.9:80 weight=2 max_fails=3 fail_timeout=60s;
server google.com weight=3 max_fails=3 fail_timeout=60s;
server ya.ru backup;
keepalive 8;
}