Keepalived

安装

dnf install -y keepalived

配置

MASTER /etc/keepalived/keepalived.conf

! Configuration File for keepalived
global_defs {
    router_id nginx-ha-21
}

vrrp_script nginx_check 
{
    script "/usr/libexec/keepalived/check-nginx-status"
    interval 3
}

vrrp_instance vi_nginx {
    state MASTER
    interface eth0
    virtual_router_id 18
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass h3m5Ewvk
    }

    track_script {
        nginx_check weight 0
    }

    virtual_ipaddress {
        192.168.20.18 dev eth0
    }
}

BACKUP /etc/keepalived/keepalived.conf

! Configuration File for keepalived
global_defs {
    router_id nginx-ha-22
}

vrrp_script nginx_check 
{
    script "/usr/libexec/keepalived/check-nginx-status"
    interval 3
}

vrrp_instance vi_nginx {
    state BACKUP
    interface eth0
    virtual_router_id 18
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass h3m5Ewvk
    }

    track_script {
        nginx_check weight 0
    }
    
    virtual_ipaddress {
        192.168.20.18 dev eth0
    }
}

配置检测脚本 /usr/libexec/keepalived/check-nginx-status

#! /bin/bash
http_url="localhost/nginx-status"
http_code=$(curl -sq -m 5 -o /dev/null $http_url -w %{http_code})

test $http_code = 200 && exit 0 || exit 1

配置权限及SELinux标签

chmod 755 /usr/libexec/keepalived/check-nginx-status

chcon -u system_u -t keepalived_unconfined_script_exec_t /usr/libexec/keepalived/check-nginx-status

防火墙

查看防火墙运行状态

firewall-cmd --state

添加规则

firewall-cmd --add-rich-rule='rule protocol value="vrrp" family=ipv4 destination address=224.0.0.18 accept' --permanent
firewall-cmd --reload

查看规则

firewall-cmd --list-all

启动

systemctl start  keepalived
systemctl enable keepalived
systemctl status keepalived