Nginx+keepalived的高可用集群(三、Keepalived高可用部署)

1.下载

Keepalived官方下载地址： http://www.keepalived.org/download.html

本次下载的是keepalived-1.4.4.tar.gz

上传到服务器后解压到当前目录：

tar -zxvf keepalived-1.4.4.tar.gz

2.安装

进入keepalived-1.4.4目录编译并安装

#进入keepalived-1.4.4目录
cd  keepalived-1.4.4
#检查依赖库是否正确
./configure --prefix=/etc/keepalived
#编译并安装
make && make install　

 

复制文件并创建软连接

因为没有用默认安装，需自行移动文件

mkdir /etc/keepalived
cp /usr/local/keepalived/etc/keepalived/keepalived.conf   /etc/keepalived/
cp /usr/local/keepalived-1.4.4/keepalived/etc/init.d/keepalived    /etc/rc.d/init.d/keepalived
cp /usr/local/keepalived/etc/sysconfig/keepalived   /etc/sysconfig/keepalived
ln -s /home/bship/keepalived /usr/sbin/

   在/etc/keepalived目录下创建Nginx启动脚本nginx_check.sh（该脚本用于检测nginx的进程）

#!/bin/bash
A=`ps -C nginx --no-header | wc -l`
if [ $A -eq 0 ];then
	/usr/local/nginx/sbin/nginx -s stop
	#尝试重新启动nginx
    /usr/bin/nginx 
	#睡眠2秒
    sleep 2  
    if [ `ps -C nginx --no-header | wc -l` -eq 0 ];then
	    #启动失败，将keepalived服务杀死。将vip漂移到其它备份节点
        killall keepalived 
    fi
fi

 并给nginx_check.sh添加执行权限

chmod +x /etc/keepalived/nginx_check.sh

3.配置文件

这里演示配置90服务器上的Keepalived，90服务器为master主机，91,92为备机。

#进入Keepalived配置目录，进行Keepalived.conf的配置
cd  /etc/keepalived

master的keepalived.conf配置如下

! Configuration File for keepalived
#全局配置 删掉了邮箱部分暂时用不到
global_defs {
   # 负载均衡唯一标识，其实就是一个标识
   router_id Nginx_90
}

#vrrp_script 定时执行脚本
vrrp_script chk_nginx {
    # 执行脚本路径
    script "/etc/keepalived/nginx_check.sh"
	# 执行间隔之间默认1S
    interval 2
	# 优先级（-254~254）默认2
    weight -20
}

#vrrp_instance 节点信息
vrrp_instance VI_1 {
   #指定节点的处所状态MASTER | BACKUP
    state MASTER
    # 网卡信息 ip address查看网卡信息
    interface ens192
    # 让master和backup在同一个虚拟路由里，id必须相同
    virtual_router_id 190
    # 优先级 谁高谁将成为master
    priority 100
    # 设置为不抢占。默认是抢占的，当高优先级的机器恢复后，会抢占低优先级的机器成为MASTER，而不抢占，则允许低优先级的机器继续成为MASTER，
    #即使高优先级的机器已经上线。如果要使用这个功能，则初始化状态必须为BACKUP。
    # nopreempt
	# 指定发送vrrp通告的时间间隔1S
    advert_int 1
    authentication {
	   # 认证方式 PASS(简单密码认证，推荐) | AH(IPSEC认证，不推荐)
        auth_type PASS
		# 密码最多8位
        auth_pass 1111
    }
	# 指定VIP地址，可虚拟多个VIP地址
    virtual_ipaddress {
        196.168.0.190
    }
       track_script {
       chk_nginx
    }
}

virtual_server 196.168.0.190 443 {
    delay_loop 6
    lb_algo rr
    lb_kind NAT
    persistence_timeout 50
    protocol TCP
}

主机和备机的配置不一致（router_id和state需要修改）

 开通端口

iptables -I INPUT -p 112 -j ACCEPT

4.启动服务

分别启动master90和backup91,92

1.启动方式一

#设置开机自动启动
systemctl enable keepalived.service 
#取消开机自动启动    
systemctl disable keepalived.service    
#启动服务
systemctl start keepalived.service    
#重启服务   
systemctl restart keepalived.service  
#停止服务  
systemctl stop keepalived.service
#查看服务状态       
systemctl status keepalived.service      　　

   启动方式二

#启动 
service keepalived start
#停止
service keepalived stop
#重启
service keepalived restart

查看keepalived的启动是否正常，显示如下界面表示正常

 

 我们通过keepalived虚拟了一个VIP的地址是196.168.0.190，我们访问这个VIP地址，成功访问到了nginx

 

 尝试把90服务上的nginx挂掉，成功实现了切换到92服务器上，这样就实现了nginx的高可用。

　　

 

 通过测试master漂移到了92服务器上