lvs+keepalived+nginx实现高性能负载均衡搭建

 

环境服务配置：

两台Nginx服务器

Nginx 主服务器  192.168.212.143

Nginx 备服务器  192.168.212.144

Lvs 虚拟VIP     192.168.212.110

前面三个一定要相同

Keepalived 环境搭建：

1.下载keepalived

wget http://www.keepalived.org/software/keepalived-1.2.18.tar.gz

2.解压安装：

tar -zxvf keepalived-1.2.18.tar.gz -C /usr/local/

3.下载插件openssl

yum install -y openssl openssl-devel（需要安装一个软件包）

4.开始编译keepalived

cd keepalived-1.2.18/ && ./configure --prefix=/usr/local/keepalived

5.make一下

make && make install

注意事项：

报错: eepalived执行./configure --prefix=/usr/local/keepalived时报错：configure: error: Popt libraries is required

出现此错误的原因：

未安装popt的开发包

解决方法：

yum install popt-devel

安装好popt的开发包。重新./configure 即可。

keepalived安装成Linux系统服务：

将keepalived安装成Linux系统服务，因为没有使用keepalived的默认安装路径（默认路径：/usr/local）,安装完成之后，需要做一些修改工作：

首先创建文件夹，将keepalived配置文件进行复制：

mkdir /etc/keepalived

cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/

然后复制keepalived脚本文件：

cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/

cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/

ln -s /usr/local/sbin/keepalived /usr/sbin/

ln -s /usr/local/keepalived/sbin/keepalived /sbin/

可以设置开机启动：chkconfig keepalived on，到此我们安装完毕!

keepalived 常用命令：

service keepalived start
service keepalived stop

keepalived 启动报错问题处理：

启动报错Starting keepalived (via systemctl):  Job for keepalived.service failed. See 'systemctl status keepalived.service' and 'journalctl -xn' for details.  
解决办法
[root@edu-proxy-01 sbin]# cd /usr/sbin/  
[root@edu-proxy-01 sbin]# rm -f keepalived   
[root@edu-proxy-01 sbin]# cp /usr/local/keepalived/sbin/keepalived  /usr/sbin/  

keepalived 配置文件实例：

vi /etc/keepalived/keepalived.conf

! Configuration File for keepalived

vrrp_script chk_nginx {
    script "/etc/keepalived/nginx_check.sh" #运行脚本，脚本内容下面有，就是起到一个nginx宕机以后，自动开启服务
    interval 2 #检测时间间隔
    weight -20 #如果条件成立的话，则权重 -20
}
# 定义虚拟路由，VI_1 为虚拟路由的标示符，自己定义名称
vrrp_instance VI_1 {
    ###MASTER 主的意思  BACKUP 从
    state MASTER #来决定主从
    interface ens33 # 绑定虚拟 IP 的网络卡，根据自己的机器填写
    virtual_router_id 121 # 虚拟路由的 ID 号， 两个节点设置必须一样
    mcast_src_ip 192.168.212.143 #填写本机ip
    priority 100 # 节点优先级,主要比从节点优先级高
    nopreempt # 优先级高的设置 nopreempt 解决异常恢复后再次抢占的问题
    advert_int 1 # 组播信息发送间隔，两个节点设置必须一样，默认 1s
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    # 将 track_script 块加入 instance 配置块
    track_script {
        chk_nginx #执行 Nginx 监控的服务
    }
    ### 虚拟IP地址配置规范 假设192.168.212.143 
    virtual_ipaddress {
        192.168.212.110 # 虚拟ip,也就是解决写死程序的ip怎么能切换的ip,也可扩展，用途广泛。可配置多个。
    }
}

nginx_check.sh 内容：

#!/bin/bash
A=`ps -C nginx –no-header |wc -l`
if [ $A -eq 0 ];then
    /usr/local/nginx/sbin/nginx
    sleep 2
    if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then
        killall keepalived
    fi
fi