user nginx;
worker_processes 1;
 
error_log /var/log/nginx/error.log warn;
pid    /var/run/nginx.pid;
 
 
events {
  worker_connections 1024;
}
 
 
http {
  include    /etc/nginx/mime.types;
  default_type application/octet-stream;
 
  log_format main '$remote_addr - $remote_user [$time_local] "$request" '
           '$status $body_bytes_sent "$http_referer" '
           '"$http_user_agent" "$http_x_forwarded_for"';
 
  access_log /var/log/nginx/access.log main;
 
  sendfile    on;
  tcp_nopush   on;
  tcp_nodelay on;
 
 
  keepalive_timeout 65;
  client_max_body_size 8192m;
 
  #gzip on;
 
  #include /etc/nginx/conf.d/*.conf;
 
 
 
  server {
 listen 80 so_keepalive=30m::;
 listen 443 default ssl;
 
 ssl_certificate /etc/nginx/ssl/server.crt;
 ssl_certificate_key /etc/nginx/ssl/portalkey.key;
 #ssl_password_file /etc/nginx/ssl/ssl.pass;
 
 
    ssl_session_timeout 5m;
    ssl_protocols SSLv2 SSLv3 TLSv1;
    ssl_ciphers HIGH:!aNULL:!MD5;
    ssl_prefer_server_ciphers on;
 
 location / {
 proxy_request_buffering off;
 proxy_pass http://127.0.0.1:8011/;
 proxy_connect_timeout    180;
    proxy_send_timeout     180;
    proxy_read_timeout     180;
    send_timeout  180;
 }
 location /test1_url/ {
 proxy_pass http://127.0.0.1:8008/;
 proxy_connect_timeout    180;
    proxy_send_timeout     180;
    proxy_read_timeout     180;
    send_timeout  180;
 }
 location /test2_url/ {
 proxy_pass http://127.0.0.1:3000/;
 proxy_connect_timeout    180;
    proxy_send_timeout     180;
    proxy_read_timeout     180;
    send_timeout  180;
 }
  }
}

so_keepalive=on|off|[keepidle]:[keepintvl]:[keepcnt]

so_keepalive=30m::10
  will set the idle timeout (TCP_KEEPIDLE) to 30 minutes, leave the probe interval (TCP_KEEPINTVL) at its system default, and set the probes count (TCP_KEEPCNT) to 10 probes.