Mac Firewall 101: How to Open Specific Ports in macOS Sequoia Like a Pro
Your Mac’s built-in firewall is like an elite security guard—keeping your system safe while letting trusted apps through the gates. But what if you need to open a specific port for a web server, game, or remote access? No worries—I’ll walk you through it!
How Does the macOS Firewall Work?
Unlike traditional firewalls that let you open and close individual ports, macOS manages things per application. That means most of the time, apps request access, and you either approve or deny them (like a firewall bouncer).
But if you’re a developer, IT pro, or just love getting under the hood, you might need to manually open a port. Let’s do it the right way.
Allowing an App Through the macOS Firewall
This is the easiest method and works for most users:
1. Go to System Settings > Network > Firewall.
2. Click Options… (you may need to unlock settings with Touch ID or your password).
3. Click Add (+), then select the app you want to allow.
4. Set it to “Allow incoming connections”, then click Done.
Most users should stop here since macOS automatically handles ports for allowed apps. But if you need to open a specific port manually, read on.
Opening a Specific Port via Terminal (For Power Users 💪)
In macOS Sequoia, Apple still uses Packet Filter (PF) to control network traffic. Here’s how to open a port manually:
1️⃣ Create a PF Rule
1. Open Terminal (Command + Space, type “Terminal,” hit Enter).
2. Edit the PF configuration file:
sudo nano /etc/pf.conf
3. Add this line at the end of the file (replace 8080 with your desired port):
pass in proto tcp from any to any port 8080
4. Save and exit: Press Control + X, then Y, then Enter.
2️⃣ Activate the Rule
Now, apply the new settings:
sudo pfctl -f /etc/pf.conf
sudo pfctl -e
Want to disable the firewall rule later? Use:
sudo pfctl -d
3️⃣ Verify That the Port Is Open
To check if the port is open, use:
sudo lsof -i :8080
If an app is actively using the port, it will show up in the list.
Stealth Mode: Be a Ghost on the Network 👻
Want to make your Mac invisible to network scans and pings? Enabling Stealth Mode helps prevent hackers from detecting your device.
Here’s how to turn it on:
1. Go to System Settings > Network > Firewall.
2. Click Options…
3. Toggle Stealth Mode to ON.
💡 Pro Tip: This won’t affect normal web browsing but will block certain network discovery features like AirDrop and Bonjour.
Final Thoughts
For most users, letting macOS handle firewall settings is the easiest and safest option. But if you need to manually open a port, now you know how! 🎯
