Keepalived常用配置及脚本

keepalived配置文件路径：/etc/keepalived/keepalived.conf
更多keepalived介绍请参考：http://blog.csdn.net/huwh_/article/details/77113410

1. keepalived.conf

1.1. MASTER（主机配置）

global_defs {    router_id wae-proxy-keepalived}vrrp_script check_nginx {    script "/etc/keepalived/scripts/check_nginx.sh"     interval 3      weight 2   }vrrp_instance VI_1 {    state MASTER    interface eth2    virtual_router_id 15    priority 100    advert_int 1    authentication {        auth_type PASS        auth_pass wae@siqian    }    track_script {        check_nginx     }    virtual_ipaddress {        180.101.115.139        218.98.38.29    }    nopreempt    notify_master "/etc/keepalived/keepalived_notify.sh master"    notify_backup "/etc/keepalived/keepalived_notify.sh backup"    notify_fault "/etc/keepalived/keepalived_notify.sh fault"    notify_stop "/etc/keepalived/keepalived_notify.sh stop"}

1.2. BACKUP（备机配置）

global_defs {    router_id wae-proxy-keepalived}vrrp_script check_nginx {    script "/etc/keepalived/scripts/check_nginx.sh"     interval 3      weight 2   }vrrp_instance VI_1 {    state BACKUP     interface eth2    virtual_router_id 15    priority 99    advert_int 1    authentication {        auth_type PASS        auth_pass wae@siqian    }    track_script {        check_nginx     }    virtual_ipaddress {        180.101.115.139        218.98.38.29    }    nopreempt    notify_master "/etc/keepalived/keepalived_notify.sh master"    notify_backup "/etc/keepalived/keepalived_notify.sh backup"    notify_fault "/etc/keepalived/keepalived_notify.sh fault"    notify_stop "/etc/keepalived/keepalived_notify.sh stop"}

1.3. 注意事项

1、指定Nginx健康检测脚本：/etc/keepalived/scripts/check_nginx.sh
2、主备配置差别主要为（建议这么配置）：
- 主机:(state MASTER;priority 100)
- 备机：(state BACKUP;priority 99)
- 非抢占：nopreempt
或者：
- 主机:(state BACKUP;priority 100)
- 备机：(state BACKUP;priority 100)
- 默认抢占
3、指定VIP

    virtual_ipaddress {        180.101.115.139        218.98.38.29    }

4、可以指定为非抢占：nopreempt，即priority高不会抢占已经绑定VIP的机器。
5、制定绑定IP的网卡： interface eth2
6、可以指定keepalived状态变化通知

    notify_master "/etc/keepalived/keepalived_notify.sh master"    notify_backup "/etc/keepalived/keepalived_notify.sh backup"    notify_fault "/etc/keepalived/keepalived_notify.sh fault"    notify_stop "/etc/keepalived/keepalived_notify.sh stop"

7、virtual_router_id 15值，主备值一致，但建议不应与集群中其他Nginx机器上的相同

2. Nginx健康检测脚本

在Nginx配置目录下（/etc/nginx/conf.d/）增加health.conf的配置文件,该配置文件用于配置Nginx health的接口。

server {    listen       80  default_server;    server_name  localhost;    default_type text/html;    return 200 'Health';  }

Nginx健康检测脚本：/etc/keepalived/scripts/check_nginx.sh

2.1. 检查接口调用是否为200

#!/bin/shset -xtimeout=30 #指定默认30秒没返回200则为非健康，该值可根据实际调整if [ -n ${timeout} ];then    httpcode=`curl -sL -w %{http_code} -m ${timeout} http://localhost -o /dev/null`else    httpcode=`curl -sL -w %{http_code}  http://localhost -o /dev/null`fiif [ ${httpcode} -ne 200 ];then        echo `date`':  nginx is not healthy, return http_code is '${httpcode} >> /etc/keeperalived/keepalived.log        killall keepalived        exit 1else        exit 0fi

2.2. 检查Nginx进程是否运行

#!/bin/shif [ `ps -C nginx --no-header |wc -l` -eq 0 ];then        echo "$(date) nginx pid not found">>/etc/keepalived/keepalived.log        killall keepalivedfi

3. Keepalived状态通知脚本

#!/bin/bashset -xwarn_receiver=$1ip=$(cat /etc/server.info|grep IPS)warningInfo="${ip}_keepalived_changed_status_to_$1"warn-report --user admin --key=xxxx --target=${warn_receiver} ${warningInfo}echo $(date)  $1 >> /etc/keepalived/status

说明：
1. ip获取本机IP，可换成其他脚本，本例中IP获取是基于特殊环境的配置文件，其他地方不适用。
2. 告警工具根据自己指定。