### **1. Verify Current Networking and Firewall Configuration**
1. **Check IP addresses and network interfaces:**
Run the following command to get a list of network interfaces and their IP addresses.
```bash
ip addr
```
2. **Verify if iptables is installed:**
Check if iptables is available on your system.
```bash
iptables --version
```
3. **Check current iptables rules:**
List all existing rules in the firewall.
```bash
sudo iptables -L
```
---
### **2. Block Specific Ports**
You can block incoming traffic on specific ports using iptables.
1. **Block incoming traffic on port 80 (HTTP):**
This will block all HTTP traffic from reaching your server.
```bash
sudo iptables -A INPUT -p tcp --dport 80 -j DROP
```
2. **Block incoming traffic on port 443 (HTTPS):**
This will block all HTTPS traffic.
```bash
sudo iptables -A INPUT -p tcp --dport 443 -j DROP
```
3. **Verify the changes:**
List the rules to ensure that the ports are blocked.
```bash
sudo iptables -L
```
4. **Test port blocking:**
From a different machine, try to access the blocked port using
curlor a browser.You should not be able to reach the server on ports 80 or 443.