1、用户登录控制台选择数据中心后，在Uhost的主标签下点击”弹性IP”功能按钮，点击”申请IP”按钮下的”申请内网IP”。

2、选择需要申请的内网弹性IP的个数，点击”确定”后完成申请流程。

3、页面返回后展示申请到的内网弹性IP信息。

CentOS下直接用yum安装

# yum install -y keepalived

先解释下以下步骤中的几个变量（默认使用root权限）

undefined: 服务器A的内网IP

undefined: 服务器B的内网IP

undefined: 内网VIP

1、编辑/etc/keepalived/keepalived.conf

global_defs {
	router_id LVS_DEVEL
}
vrrp_instance VI_1 {
  state MASTER
  interface eth0
  #unicast peer 格式必须完全匹配！否则会起不来，必须写成三行。
  unicast_peer {
        undefined
  }
  virtual_router_id 51
  priority 100 advert_int 1
  authentication {
    auth_type PASS
    auth_pass 1111
  }
  virtual_ipaddress {
        undefined dev eth0
  }
}

2、启动keepalived

# service keepalived start

1、编辑/etc/keepalived/keepalived.conf

global_defs {
	router_id LVS_DEVEL
}
vrrp_instance VI_1 {
  state BACKUP
  interface eth0
  #unicast peer 格式必须完全匹配！否则会起不来，必须写成三行。
  unicast_peer {
  	undefined
  }
  virtual_router_id 51
  priority 90
  advert_int 1
  authentication {
    auth_type PASS
    auth_pass 1111
  }
  virtual_ipaddress {
  	undefined dev eth0
  }
}

2、启动keepalived

# service keepalived start

1、检查系统日志, 观察keepalived是否成功

# tail /var/log/messsages

2、在node1上停止掉keepalived，然后在node1和node2上分别观察IP信息

# service keepalived stop

# ip a