Windows下用Nginx+Tomcat配置集群负载均衡
Nginx是一款轻量级的web服务器/反向代理服务器,更详细的释义自己百度了。目前国内像新浪、网易等都在使用它。先说下我的服务器软件环境：
系统：windows_server_2008_standard_enterprise_and_datacenter_with_sp2_x64
当前运行的Tomcat：非安装版本Tomcat 6.0.36
就说这两个关键的吧，目前遇到的问题是访问量剧增单个tomcat已无力负载了，经常出现超时的情况。于是就计划用nginx布置负载均衡，网络上查到的资料多是介绍linux版本的nginx的布置及使用，但在windows中如果使用linux版本的nginx只能做个测试用，实际生产环境是无法使用的，会报如下的错误：
maximum number of descriptors supported by select() is 1024 while waiting for request
这是因为文件访问句柄数被限制为1024了，当访问量大时就会无法响应。去网上有查过很多资料说是修改参数worker_connections可以解决此限制，还有其它很多说修改worker_rlimit_nofile 参数等，都尝试了但都以失败告终。就在准备换其它工具时在国外的一个论坛看到了一条回复，地址不记得了，说的是有专门的windows版本的nginx，已修改了文件句柄数据的限制。后来下载后果真配置成功运行ok了。只要下载到正确的版本配置还是so easy的。以下为下载配置过程哈~~
nginx for windows官网：http://nginx-win.ecsds.eu/
nginx for windows下载载地址： http://nginx-win.ecsds.eu/download/
我下载的是nginx 1.7.7.1 WhiteRabbit.zip这个版本，太新的版本我怕不稳定。下载完毕后解压安装包，里面有个简要的更新信息和安装指南Readme nginx-win version.txt。关键信息如下：
*** Default installation instructions; * New: unzip this version with folder structure * Old: overwrite with this version * Check nginx.conf, nginx-org.conf and nginx-win.conf * Windows optimization registry file: check your current values BEFORE setting the new ones找到conf文件夹中的nginx-win.conf，把它复制一份更名为nginx.conf，然后在此文件中做配置，我的配置文件如下：
#user nobody;
# multiple workers works !
# 工作进程数：这个数值要根据服务器CPU核心数来配置，如6核12线程的cpu可以配置为6或12。
worker_processes 6;
#错误日志存放路径
#error_log logs/error.log;
#error_log logs/error.log notice;
#error_log logs/error.log info;
#pid logs/nginx.pid;
events {
#设置单个进程同时打开的最大连接数，这个值设置大些能接受较多的连接，当然这需要cpu和内存支持哦~~
worker_connections 32768;
# max value 32768, nginx recycling connections+registry optimization =
# this.value * 20 = max concurrent connections currently tested with one worker
# C1000K should be possible depending there is enough ram/cpu power
# multi_accept on;
}
http {
#include /nginx/conf/naxsi_core.rules;
include mime.types;
default_type application/octet-stream;
#log_format main '$remote_addr:$remote_port - $remote_user [$time_local] "$request" '
# '$status $body_bytes_sent "$http_referer" '
# '"$http_user_agent" "$http_x_forwarded_for"';
#access_log logs/access.log main;
# # loadbalancing PHP
# upstream myLoadBalancer {
# server 127.0.0.1:9001 weight=1 fail_timeout=5;
# server 127.0.0.1:9002 weight=1 fail_timeout=5;
# server 127.0.0.1:9003 weight=1 fail_timeout=5;
# server 127.0.0.1:9004 weight=1 fail_timeout=5;
# server 127.0.0.1:9005 weight=1 fail_timeout=5;
# server 127.0.0.1:9006 weight=1 fail_timeout=5;
# server 127.0.0.1:9007 weight=1 fail_timeout=5;
# server 127.0.0.1:9008 weight=1 fail_timeout=5;
# server 127.0.0.1:9009 weight=1 fail_timeout=5;
# server 127.0.0.1:9010 weight=1 fail_timeout=5;
# least_conn;
# }
# 在此处设置tomcat服务器信息，同样tomcat也可以不在同一主机中。这里设置了两个tomcat服务，比重是1:1了。 localhost更换为服务器的IP
upstream localhost{
#ip_hash;
server 127.0.0.1:9010 weight=1;
server 127.0.0.1:9020 weight=1;
}
sendfile off;
#tcp_nopush on;
server_names_hash_bucket_size 128;
## Start: Timeouts ##
client_body_timeout 10;
client_header_timeout 10;
keepalive_timeout 80;
send_timeout 10;
keepalive_requests 10;
## End: Timeouts ##
#gzip on;
server {
#这个很关键~~它是nginx监听的端口哦~~
listen 8080;
server_name localhost;
#charset koi8-r;
#access_log logs/host.access.log main;
# For Naxsi remove the single # line for learn mode, or the ## lines for full WAF mode
location / {
#include /nginx/conf/mysite.rules; # see also http block naxsi include line
##SecRulesEnabled;
##DeniedUrl "/RequestDenied";
##CheckRule "$SQL >= 8" BLOCK;
##CheckRule "$RFI >= 8" BLOCK;
##CheckRule "$TRAVERSAL >= 4" BLOCK;
##CheckRule "$XSS >= 8" BLOCK;
proxy_pass http://localhost;
root html;
index index.html index.htm;
}
# For Naxsi remove the ## lines for full WAF mode, redirect location block used by naxsi
##location /RequestDenied {
## return 412;
##}
## Lua examples !
# location /robots.txt {
# rewrite_by_lua '
# if ngx.var.http_host ~= "localhost" then
# return ngx.exec("/robots_disallow.txt");
# end
# ';
# }
#error_page 404 /404.html;
# redirect server error pages to the static page /50x.html
#
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
}
# proxy the PHP scripts to Apache listening on 127.0.0.1:80
#
#location ~ \.php$ {
# proxy_pass http://127.0.0.1;
#}
# pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
#
#location ~ \.php$ {
# root html;
# fastcgi_pass 127.0.0.1:9000; # single backend process
# fastcgi_pass myLoadBalancer; # or multiple, see example above
# fastcgi_index index.php;
# fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
# include fastcgi_params;
#}
# deny access to .htaccess files, if Apache's document root
# concurs with nginx's one
#
#location ~ /\.ht {
# deny all;
#}
}
# another virtual host using mix of IP-, name-, and port-based configuration
#
#server {
# listen 8000;
# listen somename:8080;
# server_name somename alias another.alias;
# location / {
# root html;
# index index.html index.htm;
# }
#}
# HTTPS server
#
#server {
# listen 443 ssl spdy;
# server_name localhost;
# ssl on;
# ssl_certificate cert.pem;
# ssl_certificate_key cert.key;
# ssl_session_timeout 5m;
# ssl_prefer_server_ciphers On;
# ssl_protocols SSLv3 TLSv1 TLSv1.1 TLSv1.2;
# ssl_ciphers ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+3DES:DH+3DES:RSA+AESGCM:RSA+AES:RSA+3DES:!aNULL:!eNULL:!MD5:!DSS;
# location / {
# root html;
# index index.html index.htm;
# }
#}
}
Tomcat的配置就比较简单了就是再复制一个改三处端口就可以了。具体自己百度了。
配置完毕运行nginx.exe和tomcat就可以验证配置情况了。
nginx启动控制我采用了网上一哥们的脚本，地址如下：
http://feitianbenyue.iteye.com/blog/1989868