说明：  Keepalived是基于vrrp协议的一款高可用软件。Keepailived有一台主服务器和多台备份服务器，在主服务器和备份服务器上面部署相同的服务配置，使用一个虚拟IP地址对外提供服务，当主服务器出现故障时，虚拟IP地址会自动漂移到备份服务器。
(Keepalived is a high availability software based on VRRP protocol. Keepailived has one master server and multiple backup servers. It deploys the same service configuration on both the master server and the backup server. Keepailived uses a virtual IP address to provide services. When the master server fails, the virtual IP address drifts automatically to the backup server.)