Update build_nat_network.sh

build_nat_network.sh

@@ -55,12 +55,13 @@ iface vmbr1 inet static
 EOF
 fi
 
-# 加载iptables并设置回源
+# 加载iptables并设置回源且允许NAT端口转发
 if ! command -v iptables &> /dev/null; then
     green "iptables 未安装，正在安装..."
     apt-get install -y iptables
 fi
 iptables -t nat -A POSTROUTING -j MASQUERADE
+sysctl net.ipv4.ip_forward=1
 
 # 重启配置
 service networking restart