---
title: "3CX Firewall Checker: How to Check 3CX Ports So Calls Stay Smooth"
description: "**Ever had a call suddenly drop, audio that only comes through on one side, or an IP Phone that fails to connect?** Don't worry, it's not necessarily 3CX's fault. It could well be that the firewall on your network isn't…"
url: "https://solusipbx.id/en/pusat-bantuan/3cx-firewall-checker-eng/"
updated: "2026-10-02"
category: Keamanan VoIP dan Troubleshoot
---

# 3CX Firewall Checker: How to Check 3CX Ports So Calls Stay Smooth

**Ever had a call suddenly drop, audio that only comes through on one side, or an IP Phone that fails to connect?** Don't worry, it's not necessarily 3CX's fault. It could well be that the firewall on your network isn't configured correctly yet.

Luckily, 3CX has a **Firewall Checker** feature that can check whether the ports it needs are open or still blocked. The process is quick and can be run straight from the 3CX dashboard.

## What Is the 3CX Firewall Checker?

The **3CX Firewall Checker** is a built-in 3CX feature that tests whether your firewall and router are allowing the connections the 3CX system needs.

If the check result is **Pass**, your network configuration is good to go. But if it comes back **Fail**, it means some port is still closed or misconfigured, and some 3CX features may not work at their best.

## Why Does the Firewall Checker Matter?

Don't underestimate it. A misconfigured firewall can cause all sorts of problems, such as:

- Inbound or outbound calls failing.
- Audio only being heard on one side (one-way audio).
- IP Phones or softphones struggling to connect.
- Video conferencing not working properly.
- Remote extensions disconnecting frequently.

That's why, right after installation or after replacing your router or firewall, it's best to run the Firewall Checker first.

## How to Run the 3CX Firewall Checker

Follow the steps below.

### 1. Log In to the 3CX Admin Console

Sign in to the **Admin Console** using an administrator account.

### 2. Open the Firewall Checker Menu

Go to:

**Dashboard → Firewall Checker**

On this page you'll see a button to start the check.

### 3. Run the Test

Click the **Run Firewall Check** button.

3CX will start testing the connections and ports used for VoIP communication.

This process usually only takes a few minutes.

### 4. Wait for It to Finish

Once it's done, you'll see one of these results:

✅ **PASS**

This means all the required ports are reachable and your firewall configuration is correct.

❌ **FAIL**

This means one or more ports are still blocked or not configured correctly.

## What the Firewall Checker Results Mean

### If the Result Is PASS

Congratulations! 🎉

It means:

- The ports are open.
- NAT is working correctly.
- 3CX is ready to use.
- The risk of call problems is much lower.

No further action is needed.

### If the Result Is FAIL

Don't panic — the usual culprits are:

- A port hasn't been opened on the firewall.
- Incorrect port forwarding.
- NAT isn't configured correctly.
- The ISP is blocking a certain port.
- The router is using Double NAT.

If it fails, double-check your firewall configuration or contact your network administrator.

## Tips to Keep the Firewall Checker Passing

To keep your check results at **PASS**, do the following:

- Use a firewall that supports VoIP.
- Make sure the ports 3CX needs are allowed.
- Avoid using Double NAT.
- Run the Firewall Checker again after changing your network configuration.
- Use a stable internet connection.

## When Should You Run the Firewall Checker?

It's a good idea to run the test:

- After installing 3CX.
- After replacing your router.
- After replacing your firewall.
- After switching ISPs.
- As soon as calls start having problems.
- After making any changes to your network configuration.

The sooner you check, the sooner any problem can be found.

> # Conclusion

The **3CX Firewall Checker** is a simple but very important feature for making sure your VoIP-based phone system runs without a hitch.

Rather than waiting for problems like choppy audio, phones failing to connect, or calls not coming through, it's better to check things from the start. It only takes a few minutes but can save a lot of time during troubleshooting later. If the result is **PASS**, your network is ready to go. If it's still **FAIL**, check your firewall configuration right away so every 3CX feature can work at its best.