LVS+Keepalived高可用群集配置案例

以下是一个 LVS+Keepalived 高可用群集配置案例：

1、环境准备

• LVS 主调度器（lvs1）：IP 地址为 192.168.8.101，心跳 IP 为 192.168.4.101
• LVS 备调度器（lvs2）：IP 地址为 192.168.8.102，心跳 IP 为 192.168.4.102
• 虚拟 IP（vip）：192.168.8.100
• Web 服务器 1（nginx1）：IP 地址为 192.168.8.103
• Web 服务器 2（nginx2）：IP 地址为 192.168.8.104
• 客户端：IP 地址为 192.168.8.1

2、配置步骤

2.1、为lvs1和lvs2配置ip地址

lvs1:配置IP地址

nmcli connection modify ens33 ipv4.method manual ipv4.addresses 192.168.8.101/24
nmcli connection modify ens36 ipv4.method manual ipv4.addresses 192.168.4.101/24
nmcli connection up ens33
nmcli connection up ens36

lvs2:配置IP地址

nmcli connection modify ens33 ipv4.method manual ipv4.addresses 192.168.8.102/24
nmcli connection modify ens36 ipv4.method manual ipv4.addresses 192.168.4.102/24
nmcli connection up ens33
nmcli connection up ens36

2.2、为lvs1和lvs2安装keepalived和ipvsadm并修改配置文件

• 安装：

yum install -y keepalived ipvsadm

• Ivs1的 keepalived 配置文件修改

!configuration file for keepalived
global_defs{
    router_id cluster1
}
vrrp_instance web{
    state master
    interface ens33
    virtual_router_id 51
    priority 255
    advert_int 1
    authentication{
        auth_type pass
        auth_pass 1111
    }
    virtual_ipaddress{
        192.168.8.100/24
    }
}
virtual_server 192.168.8.100 80{
    delay_loop 6
    lb_algo rr
    lb_kind dr
    persistence_timeout 50
    protocol tcp
    real_server 192.168.8.103 80{
        weight 1
        tcp_check{
            connect_timeout 3
            retry 3
            delay_before_retry 3
        }
    }
    real_server 192.168.8.104 80{
        weight 2
        tcp_check{
            connect_timeout 3
            retry 3
            delay_before_retry 3
        }
    }
}

• Ivs2的 keepalived 配置文件修改

! configuration file for keepalived
global_defs{
    router_id cluster2
}
vrrp_instance web{
    state backup
    interface ens33
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication{
        auth_type pass
        auth_pass 1111
    }
    virtual_ipaddress{
        192.168.8.100/24
    }
}
virtual_server 192.168.8.100 80{
    delay_loop 6
    lb_algo rr
    lb_kind dr
    persistence_timeout 50
    protocol tcp
    real_server 192.168.8.103 80{
        weight 1
        tcp_check{
            connect_timeout 3
            retry 3
            delay_before_retry 3
        }
    }
    real_server 192.168.8.104 80{
        weight 2
        tcp_check{
            connect_timeout 3
            retry 3
            delay_before_retry 3
        }
    }
}

• 重启服务：在两台lvs上输入

systemctl restart keepalived

3、为后端服务器安装 httpd

web1

安装：yum install -y httpd
写入信息：echo "hello,192.168.8.103" > /usr/share/nginx/html/index.html
启动服务：systemctl enable httpd.service --now

web2

安装：yum install -y httpd
写入信息：echo "hello,192.168.8.104" > /usr/share/nginx/html/index.html
启动服务：systemctl enable httpd.service --now

4、为后端服务器配置IP地址

web1

nmcli con mod ens33 ipv4.address 192.168.8.103/24 ipv4.gateway 192.168.8.2
nmcli con up ens33
增加虚拟接口并配置 vip：nmcli connection add type dummy ifname dummy2 ipv4.method manual ipv4.addresses 192.168.8.100/32
修改内核 arp 配置：cat >>/etc/sysctl.conf<< eof net.ipv4.conf.all.arp_ignore=1 net.ipv4.conf.all.arp_announce=2 eof
刷新配置：sysctl -p

web2

nmcli con mod ens33 ipv4.address 192.168.8.104/24 ipv4.gateway 192.168.8.2
nmcli con up ens33
增加虚拟接口并配置 vip：nmcli connection add type dummy ifname dummy2 ipv4.method manual ipv4.addresses 192.168.8.100/32
修改内核 arp 配置：cat >>/etc/sysctl.conf<< eof net.ipv4.conf.all.arp_ignore=1 net.ipv4.conf.all.arp_announce=2 eof
刷新配置：sysctl -p