# 配置Keepalived
#### 操作步骤
1. 后台执行以下命令，修改/etc/keepalived/keepalived.conf文件，配置LVS主节点keepalived。 **vi /etc/keepalived/keepalived.conf**
   ```
   ! Configuration File for keepalived
    
   global_defs {
       router_id master_node
   }
    
   local_address_group laddr_gl {
       192.168.0.157  # LVS主节点地址
   }
    
   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 {
           192.168.0.27
   }
   notify_master "/etc/keepalived/notify.sh master"
   notify_backup "/etc/keepalived/notify.sh backup"
   }
    
   # 虚拟ip 端口
   virtual_server 192.168.0.27 80 { 
       delay_loop 6
       lb_algo rr
       lb_kind FNAT
       protocol TCP
       laddr_group_name laddr_gl
   #后端服务节点
       real_server 192.168.0.3 80 {
           weight 1
           TCP_CHECK {
               connect_timeout 15
               connect_port 80
               nb_get_retry 5
               delay_before_retry 3
           }
       }
       real_server 192.168.0.46 80 {
           weight 1
           TCP_CHECK {
               connect_timeout 15
               connect_port 80
               nb_get_retry 5
               delay_before_retry 3
           }
       }
   }
   ```
   
2. 后台执行以下命令，修改/etc/keepalived/keepalived.conf文件，配置LVS备节点keepalived。 **vi /etc/keepalived/keepalived.conf**
   ```
   ! Configuration File for keepalived
    
   global_defs {
       router_id master_node
   }
    
   local_address_group laddr_gl {
       192.168.0.234  #本机地址
   }
    
   vrrp_instance VI_1 {
       state BACKUP
       interface eth0
       virtual_router_id   51
       priority 99  # 需要比主节点低
       advert_int   1
       authentication {
           auth_type PASS
           auth_pass 123456
       }
       virtual_ipaddress {
           192.168.0.27
   }
   notify_master "/etc/keepalived/notify.sh master"
   notify_backup "/etc/keepalived/notify.sh backup"
   }
    
   virtual_server 192.168.0.27 80 {
       delay_loop 6
       lb_algo rr
       lb_kind FNAT
       protocol TCP
       laddr_group_name laddr_gl
       real_server 192.168.0.3 80 {
           weight 1
           TCP_CHECK {
               connect_timeout 15
               connect_port 80
               nb_get_retry 5
               delay_before_retry 3
           }
       }
       real_server 192.168.0.46 80 {
           weight 1
           TCP_CHECK {
               connect_timeout 15
               connect_port 80
               nb_get_retry 5
               delay_before_retry 3
           }
       }
   }
   ```
   ![](https://support.huaweicloud.com/bestpractice-cloudpond/public_sys-resources/note_3.0-zh-cn.png)
   步骤[3]\~[6]，主备LVS节点均需执行。
   
3. 后台执行以下命令，修改/etc/keepalived/notify.sh文件。
   **vi /etc/keepalived/notify.sh**
   ```
   #!/bin/bash
    
   if [ $# -eq 0 ]
   then
       echo "input master/backup"
       exit 1
   fi
    
   case $1 in
   master)
           sed -i "s/#laddr_group_name/laddr_group_name/" /etc/keepalived/keepalived.conf 2>/dev/null
           systemctl reload keepalived.service
   ;;
   backup)
           if [ `grep "#laddr_group_name" /etc/keepalived/keepalived.conf|wc -l` -eq 0 ]
           then
               sed -i "s/laddr_group_name/#laddr_group_name/" /etc/keepalived/keepalived.conf 2>/dev/null
               systemctl reload keepalived.service
           fi
   ;;
   esac
   ```
   **chmod +x /etc/keepalived/notify.sh**
   
4. 执行以下命令，启动keepalived。 **systemctl start keepalived**
   
5. 执行以下命令，查看配置是否下发成功。 **ipvsadm -Ln**
   ![](https://support.huaweicloud.com/bestpractice-cloudpond/zh-cn_image_0000001484075756.png "点击放大")
   ![](https://support.huaweicloud.com/bestpractice-cloudpond/public_sys-resources/note_3.0-zh-cn.png)
   如果ipvsadm返回的服务器数量和实际不符，请排查监听后端服务器端口是否放通。
   
6. 执行以下命令，设置开机启动。
   **systemctl enable keepalived.service**