CentOS Keepalived配置指南

简介

Keepalived是一个高度可靠的集群管理工具，它可以在多个服务器之间实现负载均衡和高可用性，在CentOS系统中配置Keepalived，可以帮助您实现故障转移和负载均衡,确保服务的连续性和稳定性。

环境准备

在开始配置Keepalived之前,请确保以下环境已经准备就绪：

1. 两台CentOS服务器,分别命名为Server1和Server2。
2. 服务器之间可以互相通信,且IP地址已配置。
3. 服务器上已安装Keepalived软件包。

安装Keepalived

在Server1和Server2上分别执行以下命令安装Keepalived：

sudo yum install keepalived -y

安装完成后,可以使用以下命令查看Keepalived版本：

keepalived --version

配置Keepalived

修改Server1的Keepalived配置文件：

sudo vi /etc/keepalived/keepalived.conf

添加到配置文件中：

! Configuration File for keepalived
global_defs {
   notification_email {
     admin@example.com
   }
   notification_email_subject "Keepalived Alert: $ernes"
   notification_email_from "Keepalived <admin@example.com>"
}
vrrp_instance VI_1 {
   state MASTER
   interface eth0
   virtual_router_id 51
   priority 100
   advert_int 1
   authentication {
       auth_type PASS
       auth_pass 123456
   }
   virtual_ipaddress {
       192.168.1.100/24 dev eth0 label eth0:0
   }
}
virtual_server 192.168.1.100 80 {
   delay_loop 6
   lb_method roundrobin
   persistence_timeout 50
   protocol HTTP
   real_server 192.168.1.101 80 {
       weight 1
       HTTP_GET {
           url /index.html
           status_code 200
           Negotiate
           check
       }
   }
   real_server 192.168.1.102 80 {
       weight 1
       HTTP_GET {
           url /index.html
           status_code 200
           Negotiate
           check
       }
   }
}

修改Server2的Keepalived配置文件：

sudo vi /etc/keepalived/keepalived.conf

添加到配置文件中：

! Configuration File for keepalived
global_defs {
   notification_email {
     admin@example.com
   }
   notification_email_subject "Keepalived Alert: $ernes"
   notification_email_from "Keepalived <admin@example.com>"
}
vrrp_instance VI_1 {
   state BACKUP
   interface eth0
   virtual_router_id 51
   priority 90
   advert_int 1
   authentication {
       auth_type PASS
       auth_pass 123456
   }
   virtual_ipaddress {
       192.168.1.100/24 dev eth0 label eth0:0
   }
}
virtual_server 192.168.1.100 80 {
   delay_loop 6
   lb_method roundrobin
   persistence_timeout 50
   protocol HTTP
   real_server 192.168.1.101 80 {
       weight 1
       HTTP_GET {
           url /index.html
           status_code 200
           Negotiate
           check
       }
   }
   real_server 192.168.1.102 80 {
       weight 1
       HTTP_GET {
           url /index.html
           status_code 200
           Negotiate
           check
       }
   }
}

启动和查看Keepalived服务

在Server1和Server2上分别执行以下命令启动Keepalived服务：

sudo systemctl start keepalived

使用以下命令查看Keepalived服务状态：

sudo systemctl status keepalived

相关问答FAQs

Q1：如何查看Keepalived的虚拟IP地址？

A1：在Server1和Server2上分别执行以下命令查看虚拟IP地址：

sudo ip addr show eth0:0

Q2：如何修改Keepalived的优先级？

A2：在Keepalived配置文件中，priority参数用于设置优先级，将Server1的优先级设置为100，Server2的优先级设置为90,可以通过修改以下行实现：

priority 100
priority 90