2.11.3. 安装和配置 keepalived

流程

1. 安装 keepalived ：

   [root@haproxy]# yum install -y keepalived

2. 配置 keepalived 在两个 HAProxy 节点上：

   [root@haproxy]# vim /etc/keepalived/keepalived.conf

   在配置文件中，有一个用于检查 haproxy 进程脚本：

   vrrp_script chk_haproxy {
     script "killall -0 haproxy" # check the haproxy process
     interval 2 # every 2 seconds
     weight 2 # add 2 points if OK
   }

   接下来，主负载平衡器和备份负载平衡器上的实例使用 eno1 作为网络接口。它还分配虚拟 IP 地址，即 192.168.1.20。

   Master 负载均衡器节点

   vrrp_instance RGW {
       state MASTER # might not be necessary. This is on the Master LB node.
       @main interface eno1
       priority 100
       advert_int 1
       interface eno1
       virtual_router_id 50
       @main unicast_src_ip 10.8.128.43 80
       unicast_peer {
              10.8.128.53
              }
       authentication {
           auth_type PASS
           auth_pass 1111
       }
       virtual_ipaddress {
           192.168.1.20
       }
       track_script {
         chk_haproxy
       }
   }
   virtual_server 192.168.1.20 80 eno1 { #populate correct interface
       delay_loop 6
       lb_algo wlc
       lb_kind dr
       persistence_timeout 600
       protocol TCP
       real_server 10.8.128.43 80 { # ip address of rgw2 on physical interface, haproxy listens here, rgw listens to localhost:8080 or similar
           weight 100
           TCP_CHECK { # perhaps change these to a HTTP/SSL GET?
               connect_timeout 3
           }
       }
       real_server 10.8.128.53 80 { # ip address of rgw3 on physical interface, haproxy listens here, rgw listens to localhost:8080 or similar
           weight 100
           TCP_CHECK { # perhaps change these to a HTTP/SSL GET?
               connect_timeout 3
           }
       }
   }

   备份负载均衡器节点

   vrrp_instance RGW {
       state BACKUP # might not be necessary?
       priority 99
       advert_int 1
       interface eno1
       virtual_router_id 50
       unicast_src_ip 10.8.128.53 80
       unicast_peer {
              10.8.128.43
              }
       authentication {
           auth_type PASS
           auth_pass 1111
       }
       virtual_ipaddress {
           192.168.1.20
       }
       track_script {
         chk_haproxy
       }
   }
   virtual_server 192.168.1.20 80 eno1 { #populate correct interface
       delay_loop 6
       lb_algo wlc
       lb_kind dr
       persistence_timeout 600
       protocol TCP
       real_server 10.8.128.43 80 { # ip address of rgw2 on physical interface, haproxy listens here, rgw listens to localhost:8080 or similar
           weight 100
           TCP_CHECK { # perhaps change these to a HTTP/SSL GET?
               connect_timeout 3
           }
       }
       real_server 10.8.128.53 80 { # ip address of rgw3 on physical interface, haproxy listens here, rgw listens to localhost:8080 or similar
           weight 100
           TCP_CHECK { # perhaps change these to a HTTP/SSL GET?
               connect_timeout 3
           }
       }
   }

3. 启用并启动 keepalived 服务：

   [root@haproxy]# systemctl enable keepalived
   [root@haproxy]# systemctl start keepalived