linux-dhcp-server.txt

# Internet Sharing from Wi-Fi to Ethernet Device (Static IP)

This guide explains how to share internet from a Wi-Fi interface (`wlp226s0`) to an Ethernet-connected device (`192.168.216.98`) using `eno1np0` on a Linux system with NetworkManager.

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## ✅ Overview

- **Host Interface (Wi-Fi)**: `wlp226s0` — connected to the internet  
- **Ethernet Interface**: `eno1np0` — directly connected to the target device  
- **Target Device IP**: `192.168.216.98` — static or DHCP assigned

---

## 🛠️ Host Machine Configuration

### 1. Set up shared connection:
```bash
nmcli connection modify eno1np0 ipv4.method shared
nmcli connection modify eno1np0 ipv4.addresses 192.168.216.1/24
nmcli connection modify eno1np0 ipv4.dns 8.8.8.8
nmcli connection up eno1np0
```

### 2. Enable IP forwarding and NAT:

Edit /etc/sysctl.conf:
```bash
net.ipv4.ip_forward = 1
```

Apply it:
```bash
sudo sysctl -p
```
Set up NAT:
```bash
sudo iptables -t nat -A POSTROUTING -o wlp226s0 -j MASQUERADE
```
(Optional) Make it persistent:
```bash
sudo iptables-save > /etc/iptables/rules.v4
```