KVM虚拟化搭建nginx负载均衡 和lamp 架构（三 nginx负载均衡）

fsdfwe

                      nginx的负载均衡是通过nginx的upstream模块和proxy_pass反向代理来实现的。

依赖包及工具
yum install -y wget gcc pcre-devel zlib-devel zlib

nginx下载地址  http://nginx.org/en/download.html

第一步 安装nginx


下载
# cd /usr/local/src/
# wget http://nginx.org/download/nginx-1.10.0.tar.gz



解压
# tar zxvf nginx-1.10.0.tar.gz

# cd nginx-1.10.0
安装
# ./configure --prefix=/usr/local/nginx --with-pcre

错误
./configure: error: the HTTP rewrite module requires the PCRE library.
You can either disable the module by using --without-http_rewrite_module
option, or install the PCRE library into the system, or build the PCRE library
statically from the source with nginx by using --with-pcre=<path> option.
解决方法：
# yum install -y pcre-devel zlib-devel zlib

# make && make install && echo $?
# /usr/local/nginx/sbin/nginx
启动nginx服务

第二步 编写nginx启动脚本，并加入系统服务

[iyunv@localhost ~]# vim /etc/init.d/nginx
#!/bin/bash
# chkconfig: - 30 21
# description: http service.
# Source Function Library
. /etc/init.d/functions
# Nginx Settings
NGINX_SBIN="/usr/local/nginx/sbin/nginx"
NGINX_CONF="/usr/local/nginx/conf/nginx.conf"
NGINX_PID="/usr/local/nginx/logs/nginx.pid"
RETVAL=0
prog="Nginx"
start() {
echo -n $"Starting $prog: "
mkdir -p /dev/shm/nginx_temp
daemon $NGINX_SBIN -c $NGINX_CONF
RETVAL=$?
echo
return $RETVAL
}
stop() {
echo -n $"Stopping $prog: "
killproc -p $NGINX_PID $NGINX_SBIN -TERM
rm -rf /dev/shm/nginx_temp
RETVAL=$?
echo
return $RETVAL
}
reload(){
echo -n $"Reloading $prog: "
killproc -p $NGINX_PID $NGINX_SBIN -HUP
RETVAL=$?
echo
return $RETVAL
}
restart(){
stop
start
}
configtest(){
$NGINX_SBIN -c $NGINX_CONF -t
return 0
}
case "$1" in
start)
start
;;
stop)
stop
;;
reload)
reload
;;
restart)
restart
;;
configtest)
configtest
;;
*)
echo $"Usage: $0 {start|stop|reload|restart|configtest}"
RETVAL=1
esac
exit $RETVAL

[iyunv@LNMP html]# chmod 755 /etc/init.d/nginx
赋予执行权限
[iyunv@LNMP html]# chkconfig --add nginx
加入启动列表
[iyunv@LNMP html]# chkconfig  nginx  on
开机启动
[iyunv@LNMP html]# service nginx start
正在启动 Nginx：                                           [确定]
[iyunv@LNMP html]# service nginx stop
停止 Nginx：        [确定]
# service nginx configtest
nginx: the configuration file /usr/local/nginx/conf/nginx.conf syntax is ok
nginx: configuration file /usr/local/nginx/conf/nginx.conf test is successful

# /usr/local/nginx/sbin/nginx -t
nginx: the configuration file /usr/local/nginx/conf/nginx.conf syntax is ok
nginx: configuration file /usr/local/nginx/conf/nginx.conf test is successful

第三步 修改配置文件
# vim /usr/local/nginx/conf/nginx.conf


user nobody nobody;
worker_processes 2;
error_log /usr/local/nginx/logs/nginx_error.log crit;
pid /usr/local/nginx/logs/nginx.pid;
worker_rlimit_nofile 51200;
events
{
    use epoll;
    worker_connections 6000;
}

http
        {
    upstream myweb1 {
        server 192.168.244.143:80;
        server 192.168.244.144:80;
                }
    server {
              listen       80;
              server_name  192.168.244.145;
              location / {
                  proxy_pass http://myweb1;
                  proxy_next_upstream http_500 http_502 http_503 error timeout invalid_header;
                  proxy_set_header Host $host;
                  proxy_set_header X-Forwarded-For $remote_addr;
                         }
           }
       }