CentOS Keepalived配置

借助 Keepalived 完成VIP配置

• 在网关节点安装 Keepalived

$ yum install -y keepalived

• 编辑配置文件

  注意！当前调用健康监测脚本内容为注释状态，原因是在安装 Rainbond 前 需要确保 VIP 已经存在；在 Rainbond 安装完成之后需将注释取消，才能实现健康监测，确保 网关高可用。

  • 主节点

$ vi /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {
   router_id LVS_DEVEL
}
#vrrp_script check_gateway {
# 检测脚本
#   script "/etc/keepalived/check_gateway_status.sh"
# 执行间隔时间
#   interval 5
#}
vrrp_instance VI_1 {
                    
    #因使用非抢占模式，这里都为backup
    state BACKUP 
    #网卡设备名，通过 ifconfig 命令确定  
    interface ens6f0       
    virtual_router_id 51
    #优先级，主节点大于备节点     
    priority 100    
    advert_int 1
    #非抢占模式
    nopreempt
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        <VIP>               
     }
#     track_script {
#    check_gateway
#   }
}

• 从节点

$ vi /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {
   router_id LVS_DEVEL
}
#vrrp_script check_gateway {
# 检测脚本
#  script "/etc/keepalived/check_gateway_status.sh"
# 执行间隔时间
#  interval 5
#  }    
    vrrp_instance VI_1 {
    #因使用非抢占模式，这里都为backup
    state BACKUP 
    #网卡设备名，通过 ifconfig 命令确定   
    interface ens6f0
    virtual_router_id 51
    #优先级，主节点大于备节点   
    priority 50
    advert_int 1
    #非抢占模式
    nopreempt
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        <VIP>           
    }
#     track_script {
#    check_gateway
#   }
}

• 健康监测脚本

  扩展对网关节点健康检查的脚本，脚本的功能是当 rbd-gateway 组件停止服务，则关闭本机的 Keepalived，切换 VIP 。(主从都需操作)

$ vi /etc/keepalived/check_gateway_status.sh 

#!/bin/bash                                                                                             
/usr/bin/curl -I http://localhost:10254/healthz 

if [ $? -ne 0 ];then
                                                                   
     cat /var/run/keepalived.pid | xargs kill

fi

添加执行权限

$ chmod +x /etc/keepalived/check_gateway_status.sh

• 更改 Keepalived systemd 配置文件，添加两项配置

  添加两项参数

$  vi /lib/systemd/system/keepalived.service

# /lib/systemd/system/keepalived.service
[Unit]
Description=Keepalive Daemon (LVS and VRRP)
After=network-online.target
Wants=network-online.target
# Only start if there is a configuration file
ConditionFileNotEmpty=/etc/keepalived/keepalived.conf
[Service]
Type=forking
KillMode=process
PIDFile=/var/run/keepalived.pid
# Read configuration variable file if it is present
EnvironmentFile=-/etc/default/keepalived
ExecStart=/usr/sbin/keepalived $DAEMON_ARGS
ExecReload=/bin/kill -HUP $MAINPID
# 总是重启该服务
Restart=always
# 重启间隔时间
RestartSec=10

[Install]
WantedBy=multi-user.target

• 启动服务

  启动服务并设置开机自启动

systemctl start keepalived
systemctl enable keepalived
systemctl status keepalived

• 检测 VIP 是否启动

ip a |grep <VIP>

在进行下一步操作前请确保 VIP 已经存在，如果 VIP 不存在，请重新审查本节操作；在 Rainbond 安装完成之后请将配置文件中注释取消并重启 Keepalived 服务，实现健康监测，以此确保 网关高可用。