How to Set Up Your Own VoIP Phone System

Overview

This guide teaches you how to deploy FusionPBX, an open-source VoIP PBX system, on your Ubuntu server. You'll handle extensions, IVR menus, call routing, and SIP trunking — giving your business complete control over phone infrastructure and eliminating expensive carrier fees.

Prerequisites

A production-ready Ubuntu 24.04 LTS server (minimum 2GB RAM, 20GB disk)
A domain name for SIP registration
An external SIP trunk provider (Twilio, Telnyx, or similar)
Basic Linux command-line familiarity

Step 1: Install FusionPBX

1.1 Install FreeSWITCH Dependencies

FusionPBX is built on FreeSWITCH. Install required packages:

sudo apt update && sudo apt install -y curl wget gnupg2
sudo apt install -y postgresql postgresql-contrib

1.2 Install FusionPBX

Clone the FusionPBX repository and run the installer:

cd /opt
sudo git clone https://github.com/fusionpbx/fusionpbx.git
cd fusionpbx
sudo chmod +x -R install
sudo ./install/install.sh

The installer will prompt for PostgreSQL password and domain configuration.

1.3 Secure the Web Interface

Access FusionPBX at https://your-domain.com (username: admin, password: provided during install).

Immediately change the default password in Settings → Accounts.

Step 2: Configure Extensions

2.1 Create Your First Extension

In FusionPBX web interface: Dialplan → Extensions → Add

Extension: 1000
Enabled: Yes
Description: Main Office
Voicemail: Enable
Voicemail Password: Strong password
Caller ID Name: Your Business Name
Caller ID Number: Main phone number

Save and note the SIP credentials (username/password) for connecting a phone or softphone.

2.2 Configure SIP Phones or Softphones

Use these credentials to register:

Proxy/SIP Server: your-domain.com
Port: 5060 (or 5061 for TLS)
Username: Extension (e.g., 1000)
Password: As configured above
Display Name: Your name

Step 3: Build an IVR (Interactive Voice Response)

3.1 Create an IVR Menu

In FusionPBX: Dialplan → IVR → Add

Name: Main Menu
Greet Long: "Welcome to [Company Name]. Press 1 for sales, 2 for support, 0 for operator."
Menu Options:
- Press 1 → Route to extension 1001 (Sales)
- Press 2 → Route to extension 1002 (Support)
- Press 0 → Route to extension 1000 (Operator)

Step 4: Set Up SIP Trunking

4.1 Configure Telnyx SIP Trunk (Example)

Add gateway settings (Gateways tab):

Name: telnyx-trunk
Proxy: sip.telnyx.com
Username: Your Telnyx username
Password: Your Telnyx password
Realm: sip.telnyx.com

4.2 Create Dialplan for Outbound Calls

In FusionPBX: Dialplan → Dialplan → Add outbound route

Expression: ^(\d{10})$ (for 10-digit US numbers)
Gateway: telnyx-trunk
Action: bridge {sip_from_user=$1@sip.telnyx.com}

Step 5: Call Recording & Voicemail

5.1 Enable Call Recording

In Extensions settings, enable "Record Calls" for quality assurance and compliance.

5.2 Voicemail to Email

Configure voicemail-to-email in Settings → Email to notify users of voicemails automatically.

Step 6: Backup & Monitoring

6.1 Backup FusionPBX Configuration

sudo pg_dump -U postgres fusionpbx > /backups/fusionpbx_$(date +%Y%m%d).sql

Schedule this daily via cron.

6.2 Monitor System Health

In FusionPBX: System → System Status

Monitor active calls, registered extensions, and SIP trunk status.

Common Troubleshooting

No Inbound/Outbound Audio (One-Way Audio)

Check: 1) SIP trunk credentials correct? 2) Firewall allows RTP ports (16384-32767)? 3) NAT settings correct?

SIP Registration Fails

Verify: 1) Domain DNS resolves? 2) Port 5060/5061 open? 3) Username/password correct?

Extensions Don't Register

In FreeSWITCH console: freeswitch> sofia status to see registration status. Check logs: tail -f /var/log/freeswitch/freeswitch.log

Next Steps

Add additional extensions for team members
Create department-specific IVR menus
Integrate with CRM (Salesforce, etc.)
Set up call center features (agents, queues)
Implement call center dialer functionality

Learn More

For comprehensive hands-on training, enroll in our FusionPBX VoIP Training program.