nginx proxy_pass 和upstream值的奇怪问题

xueleixu

upstream www_test_com {
#ip_hash;
server 192.168.10.13:80 weight=1 max_fails=2 fail_timeout=30s;
server 192.168.10.14:80 weight=1 max_fails=2 fail_timeout=30s;
server 192.168.10.15:80 weight=1 max_fails=2 fail_timeout=30s;
server 192.168.10.16:80 weight=1 max_fails=2 fail_timeout=30s;

}

server {
listen 80;
server_name www.test.com 192.168.10.11;

access_log logs/www.test.com-proxy_access.log main;
# access_log off;

location / {
proxy_next_upstream http_502 http_504 error timeout invalid_header;
proxy_pass http://www_test_com;
proxy_redirect off;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
client_max_body_size 50m;
client_body_buffer_size 256k;
proxy_connect_timeout 30;
proxy_send_timeout 30;
proxy_read_timeout 60;

proxy_buffer_size 16k;
proxy_buffers 4 32k;
proxy_busy_buffers_size 64k;
proxy_temp_file_write_size 64k;
}

nginx的配置文件就是上面这样的，但是我现在我发现个奇怪的问题，那就是在我刷新页面的时候，php获取到的$_SERVER['HOST']的值有时候居然是www_test_com，按道理或者的值应该是www.test.com才对啊，这个问题困扰我很久了，如果大家知道怎么解决的话，请大家指点我一下，谢谢了！！