ifconfig：
[sean@vpnroute ~]$ ifconfig
enp2s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1.73 netmask 255.255.255.0 broadcast 192.168.1.255
inet6 fe80::ec0b:ae38:36e5:804b prefixlen 64 scopeid 0x20<link>
ether 00:e0:4c:d2:31:69 txqueuelen 1000 (Ethernet)
RX packets 2402 bytes 276939 (270.4 KiB)
RX errors 0 dropped 2 overruns 0 frame 0
TX packets 278 bytes 41664 (40.6 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
enp4s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::f85a:9d48:bbc9:9ccd prefixlen 64 scopeid 0x20<link>
ether 00:e0:4c:d2:31:6a txqueuelen 1000 (Ethernet)
RX packets 77 bytes 17028 (16.6 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 23 bytes 6396 (6.2 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
tun0: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST> mtu 1500
inet 10.117.222.6 netmask 255.255.254.0 destination 10.117.222.6
inet6 fe80::2f3d:36f7:5e2f:4c0b prefixlen 64 scopeid 0x20<link>
unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 txqueuelen 100 (UNSPEC)
RX packets 185 bytes 34148 (33.3 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 171 bytes 20199 (19.7 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
wlp3s0b1: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
ether 00:8e:f2:df:da:04 txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
路线：
[sean@vpnroute ~]$ route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 10.117.222.1 128.0.0.0 UG 0 0 0 tun0
0.0.0.0 192.168.1.254 0.0.0.0 UG 202 0 0 enp2s0
10.117.222.0 0.0.0.0 255.255.254.0 U 0 0 0 tun0
128.0.0.0 10.117.222.1 128.0.0.0 UG 0 0 0 tun0
192.168.1.0 0.0.0.0 255.255.255.0 U 202 0 0 enp2s0
213.159.14.131 192.168.1.254 255.255.255.255 UGH 0 0 0 enp2s0
目标：
Modem <--enp2s0--> Firewall <--tun0--> VPN Server
(vpnroute) |
--enp4s0--> Router <--lan--> Clients
我不知道自己到底在做什么，所以我很难解释我尝试过的事情，但是尝试以下操作似乎不起作用：
echo 1 > /proc/sys/net/ipv4/ip_forward
iptables --table nat --append POSTROUTING --out-interface tun0 -j MASQUERADE
iptables --append FORWARD --in-interface enp4s0 -j ACCEPT
我无法修改 OpenVPN 配置。