LVS / Tun principles and characteristics: https://blog.csdn.net/qq_35887546/article/details/104425264
The experiment requires three virtual machines and physical machines:
| Virtual machine name | effect | IP |
|---|---|---|
| server1 | DS | 172.25.63.1 |
| server2 | RS1 | 172.25.63.2 |
| server3 | RS2 | 172.25.63.3 |
VIP is: 172.25.63.100
Testing Services: Http ports: 80
physical machines to clients
server2 and server3 install apache, publish written documents released under the directory / var / www / html by default
Experiments using rules before emptying server1 ago:
[root@server1 ~]# ipvsadm -C
[root@server1 ~]# ipvsadm -l
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
1. Turn on the tunnel model
in server1:
[root@server1 ~]# modprobe ipip
[root@server1 ~]# ip addr show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
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: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 52:54:00:1b:f6:56 brd ff:ff:ff:ff:ff:ff
inet 172.25.63.1/24 brd 172.25.63.255 scope global eth0
valid_lft forever preferred_lft forever
inet 172.25.63.100/32 scope global eth0
valid_lft forever preferred_lft forever
inet6 fe80::5054:ff:fe1b:f656/64 scope link
valid_lft forever preferred_lft forever
3: tunl0@NONE: <NOARP> mtu 1480 qdisc noop state DOWN qlen 1 #多了隧道的模型
link/ipip 0.0.0.0 brd 0.0.0.0
2. Add to VIP ip tunnel
In server1:
[root@server1 ~]# ip addr del 172.25.63.100/32 dev eth0 #先将VIP从eth0上删除
[root@server1 ~]# ip addr add 172.25.63.100/32 dev tunl0
3. Add ipvs rule
in server1:
[root@server1 ~]# ipvsadm -A -t 172.25.63.100:80 -s rr
[root@server1 ~]# ipvsadm -a -t 172.25.63.100:80 -r 172.25.63.2:80 -i # -i表示隧道模式
[root@server1 ~]# ipvsadm -a -t 172.25.63.100:80 -r 172.25.63.3:80 -i
[root@server1 ~]# ipvsadm -l
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP server1:http rr
-> server2:http Tunnel 1 0 0
-> server3:http Tunnel 1 0 0
[root@server1 ~]# ip link set up tunl0 #激活隧道模式
Configuring RS
The same operation as in server2 and server3:
modprobe ipip
ip addr del 172.25.63.100/32 dev eth0
ip addr add 172.25.63.100/32 dev tunl0
ip link set up tunl0
Close inverse filtering rule on server2 and server3 core (in server2 example):
[root@server2 html]# sysctl -a | grep rp_filter #，查看反向过滤规则，将选项为 1 的全部改为 0
net.ipv4.conf.all.arp_filter = 0
net.ipv4.conf.all.rp_filter = 1
net.ipv4.conf.default.arp_filter = 0
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.eth0.arp_filter = 0
net.ipv4.conf.eth0.rp_filter = 1
net.ipv4.conf.lo.arp_filter = 0
net.ipv4.conf.lo.rp_filter = 0
net.ipv4.conf.tunl0.arp_filter = 0
net.ipv4.conf.tunl0.rp_filter = 1
[root@server2 html]# sysctl -w net.ipv4.conf.all.rp_filter=0
net.ipv4.conf.all.rp_filter = 0
[root@server2 html]# sysctl -w net.ipv4.conf.default.rp_filter=0
net.ipv4.conf.default.rp_filter = 0
[root@server2 html]# sysctl -w net.ipv4.conf.eth0.rp_filter=0
net.ipv4.conf.eth0.rp_filter = 0
[root@server2 html]# sysctl -w net.ipv4.conf.tunl0.rp_filter=0
net.ipv4.conf.tunl0.rp_filter = 0
[root@server2 html]# sysctl -a | grep rp_filter #选项全部为0，设置成功
net.ipv4.conf.all.arp_filter = 0
net.ipv4.conf.all.rp_filter = 0
net.ipv4.conf.default.arp_filter = 0
net.ipv4.conf.default.rp_filter = 0
net.ipv4.conf.eth0.arp_filter = 0
net.ipv4.conf.eth0.rp_filter = 0
net.ipv4.conf.lo.arp_filter = 0
net.ipv4.conf.lo.rp_filter = 0
net.ipv4.conf.tunl0.arp_filter = 0
net.ipv4.conf.tunl0.rp_filter = 0
[root@server2 html]# sysctl -p #使所有选项生效
Attention must also be the same as the above operation on server3
5. Test
Client:
[kiosk@foundation63 ~]$ curl 172.25.63.100
server3
[kiosk@foundation63 ~]$ curl 172.25.63.100
server2
[kiosk@foundation63 ~]$ curl 172.25.63.100
server3
[kiosk@foundation63 ~]$ curl 172.25.63.100
server2
Tun model represents the successful realization
