关于地址转换（NAT）模式的负载均衡群集详细配置请访问：构建基于地址转换（LVS—NAT）模式的负载均衡群集

一、开始配置DR模式LVS

准备工作：
Centos 7操作系统四台；
Centos01模拟Web1服务器：IP地址/192.168.100.10
Centos02模拟Web2服务器：IP地址/192.168.100.20
Centos03模拟NFS服务器： IP地址/192.168.100.30
Centos05模拟LVS服务器： IP地址/192.168.100.50
Windows 客户端一台；

1、配置负载调度器

1）配置虚拟IP地址（VIP）

[ ~]# cp /etc/sysconfig/network-scripts/ifcfg-ens32 
/etc/sysconfig/network-scripts/ifcfg-ens32:0   <!--复制网卡配置文件-->
[ ~]# vim /etc/sysconfig/network-scripts/ifcfg-ens32:0   
                                    <!--配置VIP地址网卡，设置VIP地址为192.168.100.253-->
TYPE=Ethernet
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=static
DEFROUTE=yes
NAME=ens32:0   <!--修改名字-->
DEVICE=ens32:0   <!--修改名字-->
ONBOOT=yes
IPADDR=192.168.100.253    <!--修改IP地址-->
NATEMASK=255.255.255.0
[ ~]# systemctl restart network   <!--重启网卡服务-->
[ ~]# ifconfig      <!--查看是否配置成功-->
ens32: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.100.50  netmask 255.255.255.0  broadcast 192.168.100.255
        inet6 fe80::20c:29ff:fe16:c54b  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:16:c5:4b  txqueuelen 1000  (Ethernet)
        RX packets 2795  bytes 1095013 (1.0 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 1371  bytes 182001 (177.7 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

ens32:0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.100.253  netmask 255.255.255.0  broadcast 192.168.100.255
        ether 00:0c:29:16:c5:4b  txqueuelen 1000  (Ethernet)

2）调整/proc相应参数

[ ~]# vim /etc/sysctl.conf    
                  <!--修改LVS服务器的内核配置文件支持DR模式-->
net.ipv4.ip_forward = 1
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.default.send_redirects = 0
net.ipv4.conf.ens32.send_redirects = 0

[ ~]# sysctl -p   <!--刷新-->

3）配置负载分配策略

[ ~]# modprobe ip_vs        <!--加载ip_vs模块-->
[ ~]# yum -y install ipvsadm   <!--安装ipvsadm工具-->
[ ~]# ipvsadm -C       <!--清除原有策略-->
[ ~]# ipvsadm -A -t 192.168.100.253:80 -s rr    <!--配置调度服务器IP地址-->
[ ~]# ipvsadm -a -t 192.168.100.253:80 -r 192.168.100.10:80 -g -w 1   
                                                   <!--添加物理服务器-->
[ ~]# ipvsadm -a -t 192.168.100.253:80 -r 192.168.100.20:80 -g -w 1  
                                                      <!--添加物理服务器-->
[ ~]# ipvsadm-save > /etc/sysconfig/ipvsadm        <!--导出策略备份-->
[ ~]# ipvsadm -ln     <!--确认群集当前策略-->
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.100.253:80 rr
  -> 192.168.100.10:80            Route   1      0          0         
  -> 192.168.100.20:80            Route   1      0          0

2、配置web节点1服务器

[ ~]# yum -y install httpd            <!--安装http服务-->
[ ~]# echo "www.benet.com" > /var/www/html/index.html          
             <!--准备测试网页，等看到负载均衡的效果后，再挂载共享存储设备-->
[ ~]# systemctl start httpd               <!--启动http服务-->
[ ~]# systemctl enable httpd           <!--设置为开机自启动-->
[ ~]# cp /etc/sysconfig/network-scripts/ifcfg-lo 
/etc/sysconfig/network-scripts/ifcfg-lo:0     <!--生成虚拟网卡-->
[ ~]# vim /etc/sysconfig/network-scripts/ifcfg-lo:0  
                                      <!--编辑虚拟网卡监听地址为lvs服务器的VIP地址-->
DEVICE=lo:0
IPADDR=192.168.100.253
NETMASK=255.255.255.255
ONBOOT=yes
[ ~]# systemctl restart network  <!--重启网卡服务-->
[ ~]# ifconfig    <!--查看配置是否生效-->
lo:0: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 192.168.100.253  netmask 255.255.255.255
        loop  txqueuelen 1  (Local Loopback)
[ ~]# vim /etc/sysctl.conf    <!--修改web服务器ARP响应-->
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.default.arp_ignore = 1
net.ipv4.conf.default.arp_announce = 2
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2
[ ~]# sysctl -p     <!--刷新-->

3、配置web节点2服务器

[ ~]# yum -y install httpd            <!--安装http服务-->
[ ~]# echo "www.accp.com" > /var/www/html/index.html          
             <!--准备测试网页，等看到负载均衡的效果后，再挂载共享存储设备-->
[ ~]# systemctl start httpd               <!--启动http服务-->
[ ~]# systemctl enable httpd           <!--设置为开机自启动-->
[ ~]# scp /etc/sysctl.conf :/etc/  
 <!--拷贝第一台web服务器/etc/sysctl.conf配置文件到第二台web服务器的/etc/目录下-->
The authenticity of host ‘192.168.100.30 (192.168.100.20)‘ can‘t be established.
ECDSA key fingerprint is SHA256:PUueT9fU9QbsyNB5NC5hbSXzaWxxQavBxXmfoknXl4I.
ECDSA key fingerprint is MD5:6d:f7:95:0e:51:1a:d8:9e:7b:b6:3f:58:51:51:4b:3b.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added ‘192.168.100.20‘ (ECDSA) to the list of known hosts.
‘s password: 
sysctl.conf   
[ ~]# scp /etc/sysconfig/network-scripts/ifcfg-lo:0  
                           <!--拷贝lo:0网卡配置文件到第二台web服务器--> :/etc/sysconfig/network-scripts/
‘s password: 
ifcfg-lo:0                                                          100%   70   177.3KB/s   00:00
[ ~]# sysctl -p   <!--在第二台web服务器更新配置-->
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.default.arp_ignore = 1
net.ipv4.conf.default.arp_announce = 2
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2
[ ~]# systemctl restart network  <!--第二台web服务器重启网卡服务-->

4、客户端访问

客户端配置和服务器同网段IP地址，浏览器访问http://192.168.100.253

关闭浏览器删除缓存，重新访问就会得到一个新的页面，实现了负载均衡

二、安装NFS共享存储

1、配置NFS

[ ~]# yum -y install rpcbind nfs-utils   <!--安装NFS系统-->
[ ~]# mkdir /web   <!--创建共享网站根目录文件-->
[ ~]# echo "www.nfs.com" > /web/index.html  <!--网站主页写入测试数据-->
[ ~]# vim /etc/exports      <!--修改nfs主配置文件共享/web目录，
允许100.10读取共享目录， 100.20允许读取和写入共享目录-->
/web    192.168.100.10(ro) 192.168.100.20(rw)
[ ~]# systemctl start rpcbind  <!--启动rpcbind-->
[ ~]# systemctl start nfs   <!--启动nfs服务-->
[ ~]# systemctl enable rpcbind  <!--设置开机自动启动-->
[ ~]# systemctl enable nfs   <!--设置开机自动启动-->
[ ~]# showmount -e 192.168.100.30   <!--查看共享目录-->
Export list for 192.168.100.30:
/web 192.168.100.20,192.168.100.10

2、Web节点1服务器挂载共享目录

[ ~]# mount 192.168.100.30:/web /var/www/html/
                             <!--挂载共享目录到网站服务器的根目录-->
[ ~]# cat /var/www/html/index.html  <!--查看是否挂载成功-->
www.nfs.com
[ ~]# systemctl restart httpd <!--重启httpd服务-->

3、Web节点2服务器挂载共享目录

[ ~]# mount 192.168.100.30:/web /var/www/html/ 
                                            <!--挂载共享目录到网站服务器的根目录-->
[ ~]# cat /var/www/html/index.html  <!--查看是否挂载成功-->
www.nfs.com
[ ~]# systemctl restart httpd <!--重启httpd服务-->

4、客户端访问

使用tail -f /var/log/httpd/access.log查看访问成功日志，一定要想监听再去访问才可以看到效果

5、配置自动挂载NFS

1）web节点1服务器

[ ~]# vim /etc/fstab
192.168.100.30:/web /var/www/html/                                nsf     defaults        0 0

2）web节点2服务器

[ ~]# vim /etc/fstab
192.168.100.30:/web /var/www/html/                                nsf     defaults        0 0

—————— 本文至此结束，感谢阅读 ——————