让 Debian 服务器变成一个内网上外网的路由器

1 目标

使内网主机通过网关主机访问外网。

2 前置条件

2.1 网关主机 Router

两块网卡：

2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 08:00:27:c8:27:4f brd ff:ff:ff:ff:ff:ff
inet 10.0.2.15/24 brd 10.0.2.255 scope global dynamic enp0s3
valid_lft 86025sec preferred_lft 86025sec
inet6 fe80::a00:27ff:fec8:274f/64 scope link
valid_lft forever preferred_lft forever
3: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 08:00:27:4a:27:99 brd ff:ff:ff:ff:ff:ff
inet 192.168.56.111/24 brd 192.168.56.255 scope global dynamic enp0s8
valid_lft 508sec preferred_lft 508sec
inet6 fe80::a00:27ff:fe4a:2799/64 scope link
valid_lft forever preferred_lft forever

10.0.2.15 可以上外网

192.168.56.111 为内网卡

2.2 客户机 Client

2: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 08:00:27:79:02:15 brd ff:ff:ff:ff:ff:ff
inet 192.168.56.113/24 brd 192.168.56.255 scope global enp0s8
valid_lft forever preferred_lft forever
inet6 fe80::a00:27ff:fe79:215/64 scope link
valid_lft forever preferred_lft forever

3 开工

让 Debian 服务器变成一个内网上外网的路由器

原文：https://www.cnblogs.com/mouseleo/p/13939820.html