Linux学习-LVS之NAT模型部署

以下实例通过Vmware下Centos7系统上部署

环境准备

1. 准备3台centos7虚拟机
2. Director Server：VIP:192.168.88.101，DIP：172.16.1.3
3. Real Server1(web服务器)：RIP1：172.16.1.2 网关(指向Director Server)：172.16.1.3
4. Real Server2(web服务器)：RIP2：172.16.1.4 网关(指向Director Server)：172.16.1.3

基本配置(网络)

#--------Director配置
[root@ds ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:48:d3:cd brd ff:ff:ff:ff:ff:ff
    inet 192.168.88.101/24 brd 192.168.88.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::a03d:1c5b:d3d8:111c/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
3: ens37: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:48:d3:d7 brd ff:ff:ff:ff:ff:ff
    inet 172.16.1.3/24 brd 172.16.1.255 scope global noprefixroute ens37
       valid_lft forever preferred_lft forever
    inet6 fe80::7586:86b3:e6bd:c477/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
#---------RS1网络配置
[root@rs1 ~]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.16.1.2  netmask 255.255.255.0  broadcast 172.16.1.255
        inet6 fe80::2792:a1c1:4941:9616  prefixlen 64  scopeid 0x20<link>
        inet6 fe80::b28c:edf9:5114:7241  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:f6:fc:bd  txqueuelen 1000  (Ethernet)
        RX packets 322  bytes 53537 (52.2 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 376  bytes 39955 (39.0 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
#查看网关配置
[root@rs1 ~]# ip route
default via 172.16.1.3 dev ens33 proto static metric 100 
172.16.1.0/24 dev ens33 proto kernel scope link src 172.16.1.2 metric 100 
#--------RS2网络配置
[root@rs2 ~]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.16.1.4  netmask 255.255.255.0  broadcast 172.16.1.255
        inet6 fe80::2792:a1c1:4941:9616  prefixlen 64  scopeid 0x20<link>
        inet6 fe80::8a17:99a0:3797:98ee  prefixlen 64  scopeid 0x20<link>
        inet6 fe80::b28c:edf9:5114:7241  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:90:1b:3e  txqueuelen 1000  (Ethernet)
        RX packets 297  bytes 48616 (47.4 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 358  bytes 34366 (33.5 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
#查看网关配置
[root@rs2 ~]# ip route list
default via 172.16.1.3 dev ens33 proto static metric 100 
172.16.1.0/24 dev ens33 proto kernel scope link src 172.16.1.4 metric 100 

在DS安装ipvsadm

[root@ds ~]# yum install -y ipvsadm
#设置网络转发
[root@ds ~]# cat /proc/sys/net/ipv4/ip_forward
1
#如网络转发没打开，则手动配置，并通过sysctl -p 使之生效
[root@ds ~]# cat /etc/sysctl.d/ip_net.conf 
net.ipv4.ip_forward = 1
#配置ipvs规则
#添加集群
[root@ds ~]# ipvsadm -A -t 192.168.88.101:80 -s rr
[root@ds ~]# ipvsadm -L -n
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.88.101:80 rr
#添加RS主机
[root@ds ~]# ipvsadm -a -t 192.168.88.101:80 -r 172.16.1.2 -m
[root@ds ~]# ipvsadm -a -t 192.168.88.101:80 -r 172.16.1.4 -m
[root@ds ~]# ipvsadm -l -n
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.88.101:80 rr
  -> 172.16.1.2:80                Masq    1      0          0         
  -> 172.16.1.4:80                Masq    1      0          0   

配置RS1，RS2为web服务器

#在RS1和RS2两台服务器上安装nginx或httpd
#httpd编译安装--https://blog.csdn.net/xuwenpeng/article/details/115679566
#通过yum install -y httpd安装即可
#nginx编译安装--https://blog.csdn.net/xuwenpeng/article/details/116557439
#通过yum install -y nginx安装即可
#安装完成后启动nginx或httpd服务，实现以nginx为例
#在RS1，RS2启动nginx服务
[root@rs1 ~]# /usr/local/nginx/sbin/nginx 
[root@rs2 ~]# /usr/local/nginx/sbin/nginx

#修改RS1和RS2主页
[root@rs1 ~]# cat /usr/local/nginx/html/index.html
<h1>RS1 Server</h1>
[root@rs2 ~]# cat /usr/local/nginx/html/index.html
<h1>RS2 Server</h2>
#在DS上测试RS1和RS2Web服务
[root@ds ~]# curl 172.16.1.2
<h1>RS1 Server</h1>
[root@ds ~]# curl 172.16.1.4
<h1>RS2 Server</h2>

ipvsadm命令

#-n|--numeric：基于数字格式显示地址和端口
#-c|--connection：显示ipvs连接
#--stats：输出统计数据
#--rate：速率
#--exact：显示精确值不做单位换算

[root@ds ~]# ipvsadm -L -c
IPVS connection entries
pro expire state       source             virtual            destination
TCP 01:57  TIME_WAIT   localhost:60532    localhost:http     172.16.1.2:webcache
TCP 01:55  TIME_WAIT   localhost:60530    localhost:http     172.16.1.2:webcache
[root@ds ~]# ipvsadm -L -n --stats
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port               Conns   InPkts  OutPkts  InBytes OutBytes
  -> RemoteAddress:Port
TCP  192.168.88.101:80                  18      150      106    16117    12586
  -> 172.16.1.2:8080                     8       56       40     3600     4192
  -> 172.16.1.4:8080                     2       14       10      900     104
[root@ds ~]# ipvsadm -L -n --rate
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port                 CPS    InPPS   OutPPS    InBPS   OutBPS
  -> RemoteAddress:Port
TCP  192.168.88.101:80                   0        0        0        0        0
  -> 172.16.1.2:8080                     0        0        0        0        0
  -> 172.16.1.4:8080                     0        0        0        0        
#保存ipvs规则至本地磁盘
[root@ds ~]# ipvsadm -S >/etc/sysconfig/ipvsadm
#清空ipvsadm规则
[root@ds ~]# ipvsadm -C
[root@ds ~]# ipvsadm -L -n
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
#载入ipvs规则
[root@ds ~]# ipvsadm -R < /etc/sysconfig/ipvsadm
[root@ds ~]# ipvsadm -L -n
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  127.0.0.1:80 rr
  -> 172.16.1.2:80                Masq    1      0          0         
  -> 172.16.1.4:80                Masq    1      0          0  
#删除指定的RS
[root@ds ~]# ipvsadm -d -t 192.168.88.101:80 -r 172.16.1.2      
[root@ds ~]# ipvsadm -d -t 192.168.88.101:80 -r 172.16.1.4
[root@ds ~]# ipvsadm -l -n
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.88.101:80 rr
#修改调度算法，修改成dh后，同一主机访问时，会定位至同一后端server响应
[root@ds ~]# ipvsadm -E -t 192.168.88.101:80 -s dh
[root@ds ~]# ipvsadm -L -n
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.88.101:80 dh
  -> 172.16.1.2:8080              Masq    1      0          0         
  -> 172.16.1.4:8080              Masq    1      0          0