Choosing the Right VPN Solution for Elastix

Elastix servers, historically based on CentOS 6.x (and more recent versions on CentOS 7), are deployed as headless PBX/unified-communications platforms. Administrators interact almost exclusively via SSH and the yum package manager (SysV-init on CentOS 6, systemd from CentOS 7 onward). There’s usually no full desktop environment—maybe just minimal GNOME or a web-based GUI for FreePBX—and spare CPU/RAM headroom is better devoted to Asterisk and call processing.

Because of these constraints, the ideal VPN solution for Elastix must:

• Install cleanly via yum or as an easily importable RPM, without dragging in heavy graphical dependencies.
• Offer a fully CLI-driven client, allowing scripting and integration with SysV init or systemd for automatic startup.
• Support OpenVPN and/or WireGuard protocols, both battle-tested on CentOS 6.x/7.
• Maintain strong DNS leak protection and a kill-switch that can be invoked from shell scripts.
• Avoid conflicts with SIP/RTP ports and respect the real-time performance requirements of Asterisk.

Taking all this into account, three services stand out: NordVPN, Mullvad and ProtonVPN. Below is a concise feature comparison.

Comparison Table

Deep Dive: Installing Configuring the Top Picks

Based on ease of integration with yum, minimal dependencies and rock-solid CLI tools, Mullvad and ProtonVPN are the front-runners for Elastix servers. Below are step-by-step instructions.

Mullvad VPN

Mullvad provides an official repository with a lightweight CLI tool that supports both OpenVPN and WireGuard. It works flawlessly on CentOS 6.x (with EPEL) and CentOS 7.

1. Import the GPG key and add the repo:

sudo rpm --import https://repo.mullvad.net/mullvad_pub.gpg

cat 
2. Install the client and start it:
sudo yum clean all
sudo yum install mullvad-vpn-cli

# Optional: enable auto-start (CentOS 7 )
sudo systemctl enable mullvad-daemon
sudo systemctl start mullvad-daemon

3. Authenticate and connect:
# Retrieve your Mullvad account number from your dashboard
mullvad account set ACCOUNT_NUMBER

# Choose a WireGuard server in Sweden, for example
mullvad relay set wireguard se

# Bring up the tunnel
mullvad connect

# Check status
mullvad status

ProtonVPN
ProtonVPN’s CLI also integrates via an RPM repository and supports systemd units. The tool can automatically select the fastest server or pin a location. DNS leak protection and a kill switch are built-in.
1. Add the ProtonVPN repo and import the key:
sudo yum install -y yum-utils

sudo yum-config-manager --add-repo https://repo.protonvpn.com/yum/protonvpn.repo

sudo rpm --import https://repo.protonvpn.com/public_key.asc

2. Install the ProtonVPN CLI:
sudo yum clean all
sudo yum install protonvpn-cli

3. Initialize and connect:
# First-time setup: enter your ProtonVPN credentials
protonvpn init

# Connect to the fastest available server
protonvpn c -f

# Or specify protocol/location, e.g. UDP in the UK
protonvpn c --protocol udp --cc GB

# Check status
protonvpn s

Wrapping Up
For Elastix administrators, the guiding principle is minimal overhead: choose a VPN that installs via yum, runs entirely from the shell, and doesn’t interfere with SIP/RTP timings. Mullvad and ProtonVPN nail these criteria, while NordVPN remains a solid alternative if you need an even broader global footprint. All three provide excellent DNS leak protection, scripting hooks for automated reconnect or kill-switch, and no-logs policies that align well with sensitive telephony deployments.
With either Mullvad or ProtonVPN set up on your Elastix box, you’ll secure management traffic, trunk connections or remote-office links without sacrificing the realtime performance that your PBX demands.