nginx+keepalived使用文档

第一步:

下载keepalived地址:http://www.keepalived.org/download.html

解压安装:

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

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

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

make && make install

第二步:

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!

第三步:对配置文件进行修改:vim /etc/keepalived/keepalived.conf

keepalived.conf配置文件说明:

(一)Master     

! Configuration File for keepalived

global_defs {

   router_id bhz005 ##标识节点的字符串,通常为hostname

}

## keepalived 会定时执行脚本并且对脚本的执行结果进行分析,动态调整vrrp_instance的优先级。这里的权重weight 是与下面的优先级priority有关,如果执行了一次检查脚本成功,则权重会-20,也就是由100 - 20 变成了80,Master 的优先级为80 就低于了Backup的优先级90,那么会进行自动的主备切换。

如果脚本执行结果为0并且weight配置的值大于0,则优先级会相应增加。

如果脚本执行结果不为0 并且weight配置的值小于0,则优先级会相应减少。

vrrp_script chk_nginx {

    script "/etc/keepalived/nginx_check.sh" ##执行脚本位置

    interval 2 ##检测时间间隔

    weight -20 ## 如果条件成立则权重减20(-20)

}

## 定义虚拟路由 VI_1为自定义标识。

vrrp_instance VI_1 {

state MASTER   ## 主节点为MASTER,备份节点为BACKUP

    ## 绑定虚拟IP的网络接口(网卡),与本机IP地址所在的网络接口相同(我这里是eth6)

interface eth6  

virtual_router_id 172  ## 虚拟路由ID号

    mcast_src_ip 192.168.1.172  ## 本机ip地址

    priority 100  ##优先级配置(0-254的值)

    Nopreempt  ##

    advert_int 1 ## 组播信息发送间隔,俩个节点必须配置一致,默认1s

    authentication {  

        auth_type PASS

        auth_pass bhz ## 真实生产环境下对密码进行匹配

    }

    track_script {

        chk_nginx

    }

    virtual_ipaddress {

        192.168.1.170 ## 虚拟ip(vip),可以指定多个

    }

}

(二)Backup

! Configuration File for keepalived

global_defs {

   router_id bhz006

}

vrrp_script chk_nginx {

    script "/etc/keepalived/nginx_check.sh"

    interval 2

    weight -20

}

vrrp_instance VI_1 {

    state BACKUP

    interface eth7

    virtual_router_id 173

    mcast_src_ip 192.168.1.173

    priority 90 ##优先级配置

    advert_int 1

    authentication {

        auth_type PASS

        auth_pass bhz

    }

    track_script {

        chk_nginx

    }

    virtual_ipaddress {

        192.168.1.170

    }

}

(三)nginx_check.sh 脚本:

#!/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

(四)我们需要把master的keepalived配置文件 copy到master机器(172)的 /etc/keepalived/ 文件夹下,在把backup的keepalived配置文件copy到backup机器(173)的 /etc/keepalived/ 文件夹下,最后把nginx_check.sh脚本分别copy到两台机器的 /etc/keepalived/文件夹下。

(五)nginx_check.sh脚本授权。赋予可执行权限:chmod +x /etc/keepalived/nginx_check.sh

(六)启动2台机器的nginx之后。我们启动两台机器的keepalived

  /usr/local/nginx/sbin/nginx

  service keepalived start

  ps -ef | grep nginx

  ps -ef | grep keepalived

  可以进行测试,首先看一下俩台机器的ip a 命令下 都会出现一个虚拟ip,我们可以停掉  一个机器的keepalived,然后测试,命令:service keepalived stop。结果发现当前停掉的机器已经不可用,keepalived会自动切换到另一台机器上。


(七)我们可以测试在nginx出现问题的情况下,实现切换,这个时候我们只需要把nginx的配置文件进行修改,让其变得不可用,然后强杀掉nginx进程即可,发现也会实现自动切换服务器节点。


文章来源: nginx+keepalived使用文档

人吐槽 人点赞

猜你喜欢

发表评论

用户名: 密码:
验证码: 匿名发表

你可以使用这些语言

查看评论:nginx+keepalived使用文档