--- title: How to Set Up a Basic Firewall with Uncomplicated Firewall (UFW) description: A firewall is a fundamental tool for securing your server, as it controls incoming and outgoing network traffic based on predetermined rules. For Linux servers, UFW (Uncomplicated Firewall) is a popular choice due to its simplicity and ease of use,… url: "https://truehost.com/support/knowledge-base/how-to-set-up-a-basic-firewall-with-uncomplicated-firewall-ufw/" updated: "2024-10-29" category: Cloud servers in Kenya --- # How to Set Up a Basic Firewall with Uncomplicated Firewall (UFW) A firewall is a fundamental tool for securing your server, as it controls incoming and outgoing network traffic based on predetermined rules. For Linux servers, UFW (Uncomplicated Firewall) is a popular choice due to its simplicity and ease of use, even for those new to Linux system administration Originally developed for Ubuntu, UFW has since been adopted by other Debian-based systems and even some non-Debian-based distributions, thanks to its efficiency and straightforward command structure. ### Supported Operating Systems - **Ubuntu** (all LTS and newer versions) - **Debian** (and many of its derivatives) - **Linux Mint** - **Kali Linux** - **Raspberry Pi OS** (Raspbian) On **Red Hat-based** systems like **CentOS**, **RHEL**, and **Fedora**, UFW can be installed but is less common, as these distributions typically use **firewalld** as their primary firewall tool. ### How to Set Up UFW on Your Linux Server In this article, we will use a server that has Ubuntu 22.04 installed ##### **Step 1: Update your server** - First, start by updating apckages on your server. Use the command below to do that. ``` sudo apt update ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-592.png) ##### **Step 2: Install UFW** - Run the command below to install - This command will install UFW and any required dependencies. ``` sudo apt install ufw ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-594-1024x458.png) ##### **Step 2: Set Up Default Rules** - These rules help determine the overall security level of your firewall. - It’s generally best practice to **deny all incoming connections** and **allow all outgoing connections** by default. This ensures that only the traffic you explicitly allow can access your server. **Deny Incoming Connections:** ``` sudo ufw default deny incoming ``` **Allow Outgoing Connections:** ``` sudo ufw default allow outgoing ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-595-1024x202.png) - These default policies establish a secure baseline by only allowing connections to services you specify. ##### **Step 3: Allow Specific Ports and Services** - After setting up default rules, you’ll need to allow connections to essential services. **Allow SSH (Port 22)** – SSH allows remote access to your server, so allowing this port is critical if you want to maintain access. ``` sudo ufw allow ssh ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-596.png) Alternatively, if SSH is running on a different port, replace `ssh` with the port number, for example: ``` sudo ufw allow 2222 ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-597.png) Allow HTTP and HTTPS – If your server hosts a website, you’ll need to allow HTTP (port 80) and HTTPS (port 443) traffic. ``` sudo ufw allow http sudo ufw allow https ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-598.png) **Allow Other Services** – You can specify any additional services by their port number or name. For example, to allow MySQL (port 3306) or other specific ports: ``` sudo ufw allow 3306 ``` ##### **Step 4: Enable UFW** Once you’ve defined your rules, enable UFW to activate the firewall. UFW will immediately apply the rules. ``` sudo ufw enable ``` You’ll be prompted to confirm your choice. Enabling UFW will enforce the rules you’ve configured to secure your server. ![](https://truehost.com/support/wp-content/uploads/2024/10/image-599-1024x102.png) Step 5: Verify UFW Status and Rules - After enabling UFW, check its status to ensure your rules are correctly applied: - This command provides a list of active rules, showing which ports and services are allowed or denied. ``` sudo ufw status verbose ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-600.png) ##### **Step 6: Configure IP-Based Restrictions (Optional)** - UFW can allow or deny traffic based on specific IP addresses. This is useful for restricting access to certain services or adding extra security. **Allow Connections from a Specific IP**: ``` sudo ufw allow from 192.168.1.100 ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-601.png) **Deny Connections from a Specific IP:** ``` sudo ufw deny from 192.168.1.100 ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-602.png) **Allow an IP Address on a Specific Port**: ``` sudo ufw allow from 192.168.1.100 to any port 22 ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-603.png) These rules provide more granular control, which can help limit access to critical services. **Step 7: Disable UFW (if necessary)** To turn off UFW, use the following command: ``` sudo ufw disable ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-604.png) This command disables the firewall, though you can re-enable it at any time using ``` sudo ufw enable ``` ##### **Step 8: Remove or Modify Existing Rules** To delete or modify an existing rule, first list rules by numbering them: ``` sudo ufw status numbered ``` ![](https://truehost.com/support/wp-content/uploads/2024/10/image-605-1024x309.png) To delete a specific rule, use its rule number: ``` sudo ufw delete ``` In the image below, we delete rule number 6 using ***sudo ufw delete 6*** ![](https://truehost.com/support/wp-content/uploads/2024/10/image-606.png) This is useful when you need to make adjustments to your firewall configuration. Setting up a firewall is essential for securing a server, and UFW makes it easy to implement a basic firewall configuration on Linux. By following the steps outlined here, you can limit access to essential services, control connections from specific IPs, and maintain a secure server environment with minimal configuration.