Keepalived 实现 LVS 高可用负载均衡群集

! Configuration File for keepalived

global_defs {
   router_id LVS_DEVEL
}

vrrp_instance VI_1 {
    state MASTER
    interface ens32
    virtual_router_id 50
    priority 100
    advert_int 1
    nopreempt

    authentication {
       auth_type PASS
       auth_pass 11111
    }

    virtual_ipaddress {
       192.168.31.30
    }
}

virtual_server 192.168.31.31 80 {
    delay_loop 6
    
    ! 使用 rr 调度算法
    lb_algo rr

    ! 使用 DR 直接路由工作方式
    lb_kind DR  
    
    ! 会话保持时间，单位是秒。这个选项对动态网页是非常有用的，为集群系统中的 SEEION 共享
    ! 提供了一个很好的解决方案。有了这个会话保持功能，用户的请求会一直分发到同一个服务节点，
    ! 直到超过这个会话的保持时间。 注意: 这个会话保持时间是最大无响应超时时间。如果用户一直
    ! 在操作动态页面，是不受这个时间限制的。
    persistence_timeout 50

    ! 使用转发的协议类型， 也可以是 UDP    
    protocol TCP

    ! 真实提供服务器的机器
    real_server 192.168.31.31 80 {
        ! 定义权重
        weight 3

        ! real_server 状态检测，单位为秒 
        TCP_CHECK {
            ! 表示3秒无响应超时
            connect_timeout 3
            ! 表示重试次数
            nb_get_retry 3
            ! 重试间隔
            delay_before_retry 3
        }
    }

    real_server 192.168.31.32 80 {
        weight 3
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}

! Configuration File for keepalived

global_defs {
   router_id LVS_DEVEL
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens32
    virtual_router_id 50
    priority 90
    advert_int 1

    authentication {
       auth_type PASS
       auth_pass 11111
    }

    virtual_ipaddress {
       192.168.31.30
    }
}

virtual_server 192.168.31.31 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR  
    persistence_timeout 50
    protocol TCP

    real_server 192.168.31.31 80 {
        weight 3
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.31.32 80 {
        weight 3
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}

root@lb-01:/etc/keepalived# systemctl start keepalived.service
root@lb-01:/etc/keepalived# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.31.30:80 rr persistent 50
  -> 192.168.31.31:80             Route   3      0          0
  -> 192.168.31.32:80             Route   3      0          0
root@lb-01:/etc/keepalived# ip addr show ens32
2: ens32: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:af:9c:1f brd ff:ff:ff:ff:ff:ff
    inet 192.168.31.33/24 brd 192.168.31.255 scope global ens32
       valid_lft forever preferred_lft forever
    inet 192.168.31.30/32 scope global ens32
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:feaf:9c1f/64 scope link
       valid_lft forever preferred_lft forever

#!/bin/bash
# 
# filename: lvs-vip.sh
#

VIP=192.168.31.30
INTERFACE=lo

case $1 in
  start)
      echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore
      echo 1 > /proc/sys/net/ipv4/conf/lo/arp_ignore
      echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce
      echo 2 > /proc/sys/net/ipv4/conf/lo/arp_announce
      ip addr add ${VIP}/32 brd ${VIP} dev $INTERFACE
      echo "The RS Server is Ready!"
      ;;
      
  stop)
      ip addr del ${VIP}/32 brd ${VIP} dev $INTERFACE
      echo 0 > /proc/sys/net/ipv4/conf/all/arp_ignore
      echo 0 > /proc/sys/net/ipv4/conf/lo/arp_ignore
      echo 0 > /proc/sys/net/ipv4/conf/all/arp_announce
      echo 0 > /proc/sys/net/ipv4/conf/lo/arp_announce
      echo "The RS Server is Canceled!"
      ;;

  *)
      echo $"Usage: $0 {start|stop|restart}"
      exit 1
      ;;
esac