Obsidian/05.02 Networks/Configuring UFW.md

Alias	Tag	Date	DocType	Hierarchy	TimeStamp	location	CollapseMetaTable
UFW	🖥️ Firewall	2021-10-04	Personal	NonRoot		51.514678599999996 -0.18378583926867909	true

Parent:: Selfhosting, Server Alias, Server Cloud, Server Tools, Server VPN

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^Top

 

name Save
type command
action Save current file
id Save

^button-UFWSave

 

Configuring UFW

 

title: Summary
collapse: open
Description of basic commands for UFW

 

style: number

 

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Installation and activation

#^Top  

UFW should be installed by default in Ubuntu servers. If not, see below.

 

Installation of UFW

~~~bash
sudo apt install ufw
~~~

 

Activation of UFW

~~~bash
sudo ufw status
~~~

If disabled:

~~~bash
sudo ufw enable
~~~

 

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Basic commands

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UFW rules status

~~~bash
sudo ufw status
~~~

Commands can be appended:

• verbose: details incoming/outgoing rules
• numbered: display rule numbers

 

UFW rule management

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Allow / Deny

~~~bash
sudo ufw allow/deny
~~~

Then:

Type to allow	Syntax
IP	from (ip address/range)
Port	(portnumber)/(protocol)
Service	(service name)
Protocol	proto (protocol name)

 

Rule priority

Certain rules like IP denial need to be put on top of the rule stack as UFW reads rules in order one after another. Insert the following in the command to force insertion:

~~~bash
insert 1 (or any place in the pecking order)
~~~

 

Complex rule syntax

Finer rules can be defined with the following syntax.

rule condition	syntax
connecting IP	from (ip or any)
internal IP	to (ip or any)
protocol	proto (protocol or any)
port	port (port or any)
outgoing traffic	out

 

Delete a rule

~~~bash
sudo ufw delete <rule number>
~~~

 

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Ban List management

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Ban List Folder

/etc/addip4ban/

 

Ban List Script

title: addip4ban.sh
~~~bash
#!/bin/bash

INPUT="/etc/addip4ban/blocked.ip.list"

while IFS= read -r block
do
    sudo ufw insert 1 deny from "$block"
done < "$INPUT"
~~~

 

Once written, the script needs to be executed. To prepare:

~~~bash
sudo chmod +x /etc/addip4ban/addip4ban.sh
~~~

 

Ban List Document

title: blocked.ip.list
~~~bash
< ip1 >
< ip2/range >
< ip3 >
~~~

 

Ban list Update Process

Copy/paste the new ban list into blocked.ip.list and run:

~~~bash
sudo bash /etc/addip4ban/addip4ban.sh
~~~

 

Ban List Tasks

• 🖥 Selfhosting, Configuring UFW Get IP addresses caught by Postfix %%done_del%% 🔁 every week on Saturday 📅 2024-09-14
• 🖥 Selfhosting, Configuring UFW Get IP addresses caught by Postfix %%done_del%% 🔁 every week on Saturday 📅 2024-09-07 ✅ 2024-09-08
• 🖥 Selfhosting, Configuring UFW Get IP addresses caught by Postfix %%done_del%% 🔁 every week on Saturday 📅 2024-08-31 ✅ 2024-09-01
• 🖥 Selfhosting, Configuring UFW Get IP addresses caught by Postfix %%done_del%% 🔁 every week on Saturday 📅 2024-08-24 ✅ 2024-08-24
• 🖥 Selfhosting, Configuring UFW Get IP addresses caught by Postfix %%done_del%% 🔁 every week on Saturday 📅 2024-09-14
• 🖥 Selfhosting, Configuring UFW Get IP addresses caught by Postfix %%done_del%% 🔁 every week on Saturday 📅 2024-09-07 ✅ 2024-09-08
• 🖥 Selfhosting, Configuring UFW Get IP addresses caught by Postfix %%done_del%% 🔁 every week on Saturday 📅 2024-08-31 ✅ 2024-09-01
• 🖥 Selfhosting, Configuring UFW Get IP addresses caught by Postfix %%done_del%% 🔁 every week on Saturday 📅 2024-08-24 ✅ 2024-08-24
• 🖥 Selfhosting, Configuring UFW: Update the Blocked IP list %%done_del%% 🔁 every month on Saturday 📅 2024-09-14
• 🖥 Selfhosting, Configuring UFW: Update the Blocked IP list %%done_del%% 🔁 every month on Saturday 📅 2024-09-07 ✅ 2024-09-08
• 🖥 Selfhosting, Configuring UFW: Update the Blocked IP list %%done_del%% 🔁 every month on Saturday 📅 2024-08-31 ✅ 2024-09-01
• 🖥 Selfhosting, Configuring UFW: Update the Blocked IP list %%done_del%% 🔁 every month on Saturday 📅 2024-08-24 ✅ 2024-08-24