I. Introduction

1.1 Context & Purpose

Briefly explain what you’re doing and why.
If relevant, mention a key concept (but keep it brief).

1.2 What This Covers

High-level overview of what will be discussed.
Mention any specific focus (e.g., configurations, security tests, troubleshooting).

II. Setup & Environment

2.1 Network & Tools Overview

Diagram (if applicable)
Devices, OS versions, key software used

2.2 Prerequisites / Preparations

Installed AntiX Linux system (ssh)
Router
Any assumptions about the setup.

III. Execution & Findings

3.1 Current Configuration

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Before starting, I take a look at the current network configuration.

Applying Intuitive Interface Names
After taking note of the MAC addresses, we want to use 00:03:0d:53:17:49 as WAN and 00:e0:4c:36:06:d7 as LAN.

I changed the interface names on /etc/udev/rules.d/70-persistent-net.rules
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sudo udevadm control --reload-rules
sudo udevadm trigger --subsystem-match=net

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Assign static IP Address
Updated /etc/network/interfaces and restarted the service with sudo service networking restart

auto lo
iface lo inet loopback

# WAN
auto wan0
iface wan0 inet static
        address 192.168.1.250
        netmask 255.255.255.0
        gateway 192.168.1.1
        nameserver 8.8.8.8 8.8.4.4

# LAN
auto lan0
        iface lan0 inet static
        address 172.16.0.1
        netmask 255.255.255.0

# Route to LAB network
up ip route add 10.0.0.0/24 via 172.16.0.2 dev lan0

I verified the changes with ip a and ip route command.
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Enable IP Forwarding
allowed ipv4 forwarding on /etc/sysctl.conf and applied the changes using sudo sysctl -p
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/etc/iptables/rules.v4
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Router setup
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Testing by blocking HTTP Traffic

# Log HTTP traffics
-A FORWARD -i lan0 -o wan0 --dport 80 -j LOG --log-prefix "Block_HTTP"
# Block HTTP packet
-A FORWARD -i lan0 -o wan0 --dport 80 -j DROP

sudo iptables-restore < /etc/iptables/rules.v4

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3.2 Challenges & Fixes

What issues popped up?
How did you troubleshoot and solve them?
Any commands or configurations that were adjusted?

IV. Observations & Insights

What patterns, behaviors, or unexpected results did you notice?
How effective was the implementation?

V. Considerations & Next Steps

Things to improve or optimize.
Alternative approaches to try next time.

VI. Conclusion

Final thoughts, main takeaways.
What did you gain from this?

References (if any)

Temu.com, IP Range: 151.101.0.0/22

Iptables Firewall Setup