LVS的DR模式与NAT模式的部署

LVS集群配置信息DR模式

节点关闭Networkmanager所有的节点

[root@zabbix-server ~]# systemctl stop NetworkManager.service
[root@zabbix-server ~]# systemctl disable NetworkManager.service

lvs机器上创建一个子接口

[root@centos network-scripts]# cat ifcfg-eno16777728:0
TYPE=Ethernet
BOOTPROTO=static
DEFROUTE=yes
DEVICE=eno16777728:0
ONBOOT=yes
DNS1=192.168.40.2
IPADDR=192.168.40.100
PREFIX=24
GATEWAY=192.168.40.2
[root@centos network-scripts]# systemctl restart network
[root@centos network-scripts]# ifconfig
eno16777728: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.40.25  netmask 255.255.255.0  broadcast 192.168.40.255
        inet6 fe80::20c:29ff:feda:abcb  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:da:ab:cb  txqueuelen 1000  (Ethernet)
        RX packets 50417  bytes 71989175 (68.6 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 14742  bytes 1029561 (1005.4 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

eno16777728:0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.40.100  netmask 255.255.255.0  broadcast 192.168.40.255
        ether 00:0c:29:da:ab:cb  txqueuelen 1000  (Ethernet)

关闭广播功能

[root@centos ~]# grep -v "#" /etc/sysctl.conf
net.ipv4.conf.all.send_redirects=0
net.ipv4.conf.default.send_redirects=0
net.ipv4.conf.eno16777728.send_redirects=0
[root@centos ~]# sysctl -p

安装软件

[root@centos ~]# yum install -y ipvsadm
[root@centos ~]# modprobe ip_vs
[root@centos ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
[root@centos ~]#

配置服务器1和2完全一致

[root@zabbix-server network-scripts]# cat ifcfg-lo:0
DEVICE=lo:0
IPADDR=192.168.40.100
NETMASK=255.255.255.255
NETWORK=127.0.0.0
# If you're having problems with gated making 127.0.0.0/8 a martian,
# you can change this to something else (255.255.255.255, for example)
BROADCAST=127.255.255.255
ONBOOT=yes
NAME=loopback
[root@zabbix-server ~]# grep -v "#" /etc/sysctl.conf
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
[root@zabbix-server ~]# sysctl -p
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
[root@zabbix-server ~]# ifup lo:0
[root@zabbix-server ~]# ifconfig
lo:0: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 192.168.40.100  netmask 255.255.255.255
        loop  txqueuelen 0  (Local Loopback)
[root@zabbix-server ~]# route add -host 192.168.40.100 dev lo:0
[root@zabbix-server ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.40.2    0.0.0.0         UG    100    0        0 eno16777                                                                                                         736
192.168.40.0    0.0.0.0         255.255.255.0   U     100    0        0 eno16777                                                                                                         736
192.168.40.100  0.0.0.0         255.255.255.255 UH    0      0        0 lo
[root@zabbix-server ~]#

访问测试

LVS配置规则测试

[root@centos ~]# ipvsadm -A -t 192.168.40.100:80 -s rr
[root@centos ~]# ipvsadm -a -t 192.168.40.100:80 -r 192.168.40.23:80 -g
[root@centos ~]# ipvsadm -a -t 192.168.40.100:80 -r 192.168.40.24:80 -g
[root@centos ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.40.100:80 rr
  -> 192.168.40.23:80             Route   1      0          0
  -> 192.168.40.24:80             Route   1      0          0
[root@centos ~]#

LVS集群配置信息NAT模式

角色	IP地址
lvs负载均衡	192.168.40.25/24 10.10.10.11/24
web服务器1	192.168.40.23/24
web服务器2	192.168.40.24/24

所有的节点关闭NetworkManager防火墙和selinux

[root@zabbix-server ~]# systemctl stop NetworkManager.service
[root@zabbix-server ~]# systemctl disable NetworkManager.service
[root@zabbix-server ~]# systemctl stop firewalld.service
[root@zabbix-server ~]# setenforce 0

lvs负载均衡

[root@centos ~]# echo "1" > /proc/sys/net/ipv4/ip_forward
[root@centos ~]# sysctl -p
[root@centos ~]# yum install -y ipvsadm
[root@centos ~]# systemctl start ipvsadm
[root@centos ~]# iptables -t nat -A POSTROUTING -s 192.168.40.0/24 -o eno16777728 -j SNAT --to-source 10.10.10.11
[root@centos ~]# ipvsadm -A -t 10.10.10.11:80 -s rr
[root@centos ~]# ipvsadm -a -t 10.10.10.11:80 -r 192.168.40.23:80 -m
[root@centos ~]# ipvsadm -a -t 10.10.10.11:80 -r 192.168.40.24:80 -m
[root@centos ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  10.10.10.11:80 rr
  -> 192.168.40.23:80             Masq    1      0          0
  -> 192.168.40.24:80             Masq    1      0          0
[root@centos ~]#

所有服务器端

将网关换成为lvs另外一张网卡的ip

[root@zabbix-server network-scripts]# grep -i "gateway" ifcfg-eno16777736
GATEWAY=192.168.40.25
[root@zabbix-server network-scripts]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.40.25   0.0.0.0         UG    100    0        0 eno16777736
192.168.40.0    0.0.0.0         255.255.255.0   U     100    0        0 eno16777736
[root@zabbix-server network-scripts]#

访问测试

总结：在生产使用中DR模式比NAT更加的优秀，因为它能处理更多的响应。处理相同的响应的资源消耗比NAT模式更加的低。