# OpenWrt NAT設定

<p class="callout info">**若在防火牆區域勾選NAT或IP動態偽裝，則會上下行都會使用OpenWrt本身IP，若NAT後主機則無法取得真實IP**</p>

#### **基本NAT設定**  


**勾選NAT內部主機即可外連**

[![image.png](https://note.homesitetw.com/uploads/images/gallery/2025-07/scaled-1680-/image.png)](https://note.homesitetw.com/uploads/images/gallery/2025-07/image.png)

#### **只需內部主機對外NAT**

**取消勾選NAT，新增NAT規則**

**來源位址輸入內部網段**

[![image.png](https://note.homesitetw.com/uploads/images/gallery/2025-07/scaled-1680-/1TJimage.png)](https://note.homesitetw.com/uploads/images/gallery/2025-07/1TJimage.png)

#### **iptables 指令**

**172.20.10.0/24對外br-lan介面進行NAT**

```
iptables -A POSTROUTING -t nat -s 172.20.10.0/255.255.255.0 -o br-lan -j MASQUERADE
```