Linux路由

实现A与B跨三网段互相访问

• 环境说明：
• 五台机器，客户端：client1、client2，充当路由：centos6.10、srv1、srv2
• centos6.10：vmnet3、4，srv1：vmnet4、5，srv2：vmnet5、6

• client1：vmnet3、client2：vmnet6

  
  最终实现

虚拟机网卡信息

实现配置

#R1
[root@R1 ~]$vim /etc/sysconfig/network-scripts/ifcfg-eth2
DEVICE=eth2
NAME=vmnet3
BOOTPROTO=static
IPADDR=192.168.1.254
PREFIX=24
ONBOOT=yes
[root@R1 ~]$vim /etc/sysconfig/network-scripts/ifcfg-eth1
DEVICE=eth1
NAME=vmnet4
BOOTPROTO=static
IPADDR=192.168.10.1
PREFIX=24
ONBOOT=yes
[root@R1 ~]$ service NetworkManager stop
[root@R1 ~]$ service network restart
[root@R1 ~]$ route add -net 172.16.1.0/24 gw 192.168.10.254 dev eth1
[root@R1 ~]$ route add -net 1.1.1.0/24 gw 192.168.10.254 dev eth1
[root@R1 ~]$ sysctl -w net.ipv4.ip_forward=1
[root@R1 ~]$ route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 eth2
172.16.1.0      192.168.10.254  255.255.255.0   UG    0      0        0 eth1
192.168.139.0   0.0.0.0         255.255.255.0   U     0      0        0 eth0
1.1.1.0         192.168.10.254  255.255.255.0   UG    0      0        0 eth1
192.168.10.0    192.168.10.254  255.255.255.0   UG    0      0        0 eth1
192.168.10.0    0.0.0.0         255.255.255.0   U     0      0        0 eth1
169.254.0.0     0.0.0.0         255.255.0.0     U     1002   0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1003   0        0 eth2
169.254.0.0     0.0.0.0         255.255.0.0     U     1004   0        0 eth1
0.0.0.0         192.168.139.2   0.0.0.0         UG    0      0        0 eth0
    
#R2
[root@R2 ~]# vim /etc/sysconfig/network-scripts/ifcfg-eth1
DEVICE=eth1
NAME=vmnet4            
BOOTPROTO=none
IPADDR=172.16.1.253
PREFIX=24
ONBOOT=yes
[root@R2 ~]# vim /etc/sysconfig/network-scripts/ifcfg-eth2
DEVICE=eth2
NAME=vmnet5            
BOOTPROTO=none
IPADDR=172.16.1.253
PREFIX=24
ONBOOT=yes
[root@R2 ~]# systemctl stop NetworkManager
[root@R2 ~]# systemctl restart network
[root@R2 ~]# route add -net 192.168.1.0/24 gw 192.168.10.1 dev eth1
[root@R2 ~]# route add -net 1.1.1.0/24 gw 172.16.1.254 dev eth2
[root@R2 ~]$ sysctl -w net.ipv4.ip_forward=1
[root@R2 ~]#route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.139.2   0.0.0.0         UG    100    0        0 eth0
1.1.1.0         172.16.1.254    255.255.255.0   UG    0      0        0 eth2
172.16.1.0      0.0.0.0         255.255.255.0   U     102    0        0 eth2
192.168.1.0     192.168.10.1    255.255.255.0   UG    0      0        0 eth1
192.168.10.0    0.0.0.0         255.255.255.0   U     101    0        0 eth1
192.168.122.0   0.0.0.0         255.255.255.0   U     0      0        0 virbr0
192.168.139.0   0.0.0.0         255.255.255.0   U     100    0        0 eth0

#R3
[root@R3 ~]$ vim /etc/sysconfig/network-scripts/ifcfg-eth1
DEVICE=eth1
NAME=vmnet5
BOOTPROTO=none
IPADDR=172.16.1.254
PREFIX=24
ONBOOT=yes
[root@R3 ~]$ vim /etc/sysconfig/network-scripts/ifcfg-eth2
DEVICE=eth2
NAME=vmnet6
BOOTPROTO=none
IPADDR=1.1.1.254
PREFIX=24
ONBOOT=yes
[root@R3 ~]$ systemctl stop NetworkManager
[root@R3 ~]$ systemctl restart network
[root@R3 ~]$ route add -net 192.168.10.0/24 gw 172.16.1.253 dev eth1
[root@R3 ~]$ route add -net 192.168.1.0/24 gw 172.16.1.253 dev eth1
[root@R3 ~]$ sysctl -w net.ipv4.ip_forward=1
[root@R3 ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.139.2   0.0.0.0         UG    0      0        0 eth0
1.1.1.0         0.0.0.0         255.255.255.0   U     0      0        0 eth2
169.254.0.0     0.0.0.0         255.255.0.0     U     1002   0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1003   0        0 eth1
169.254.0.0     0.0.0.0         255.255.0.0     U     1004   0        0 eth2
172.16.0.0      0.0.0.0         255.255.0.0     U     0      0        0 eth1
192.168.1.0     172.16.1.253    255.255.255.0   UG    0      0        0 eth1
192.168.10.0    172.16.1.253    255.255.255.0   UG    0      0        0 eth1
192.168.122.0   0.0.0.0         255.255.255.0   U     0      0        0 virbr0
192.168.139.0   0.0.0.0         255.255.255.0   U     0      0        0 eth0

测试

#client1:
ip addr add 192.168.1.7/24 dev eth0
route add default gw 192.168.1.254
ping -c3 1.1.1.1

image.png

#client2:
ip addr add 1.1.1.1/24 dev eth0
route add default gw 1.1.1.1
ping -c3 192.168.1.7

image.png