OpenVPN Setup for Linux

Complete guide to configuring OpenVPN on your Linux system

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πŸ“‹ Before You Begin

Ensure you have your CodaMail VPN credentials ready. You'll need your VPN username and password (different from your email login) to connect to our secure VPN servers.

Important: All VPN and proxy servers are under the cotse.net domain. The codamail.com domain is exclusively for email services.

πŸ“¦ Step 1: Install OpenVPN

Distribution-Specific Installation:

🎩 Red Hat/Fedora/CentOS:

sudo dnf install openvpn
sudo yum install openvpn (older versions)

🐧 Ubuntu/Debian:

sudo apt update
sudo apt install openvpn

🦎 openSUSE:

sudo zypper install openvpn

🏹 Arch Linux:

sudo pacman -S openvpn

πŸ“₯ Step 2: Download Configuration Files

Download one or more of the following OpenVPN configuration files to your Linux system:

πŸ‡¬πŸ‡§ London Server

Server: london.cotse.net
Config File: london.ovpn
Location: United Kingdom

πŸ‡ΊπŸ‡Έ Denver Server

Server: denver.cotse.net
Config File: denver.ovpn
Location: United States (Colorado)

πŸ‡³πŸ‡± Amsterdam Server

Server: amsterdam.cotse.net
Config File: amsterdam.ovpn
Location: Netherlands

πŸ’» Step 3A: Command Line Setup (Recommended)

Configuration Preparation:

Create a directory for VPN configurations:
mkdir ~/vpn-configs
Move your downloaded .ovpn files to this directory:
mv ~/Downloads/*.ovpn ~/vpn-configs/

Create Credential File:

Create a file to store your VPN credentials:
nano ~/vpn-configs/auth.txt
Add your credentials (one per line):
your-vpn-username
your-vpn-password
Secure the file: chmod 600 ~/vpn-configs/auth.txt

Update Configuration File:

Edit your .ovpn file to use the credential file:
nano ~/vpn-configs/london.ovpn
Add this line: auth-user-pass auth.txt
Save and exit the editor

πŸ–₯️ Step 3B: NetworkManager GUI Setup (Alternative)

Install NetworkManager OpenVPN Plugin:

Ubuntu/Debian: sudo apt install network-manager-openvpn-gnome
Fedora: sudo dnf install NetworkManager-openvpn-gnome
openSUSE: sudo zypper install NetworkManager-openvpn-gnome
Arch: sudo pacman -S networkmanager-openvpn

Import Configuration:

Open your network settings (varies by desktop environment)
Click "+" or "Add Connection"
Select "Import a saved VPN configuration"
Browse to your .ovpn file and import it
Enter your VPN username and password
Click "Save" or "Apply"

πŸš€ Step 4: Connect to VPN

Command Line Connection:

Connect to the VPN server:
sudo openvpn --config ~/vpn-configs/london.ovpn
The connection will run in the foreground
Press Ctrl+C to disconnect
For background operation: sudo openvpn --config ~/vpn-configs/london.ovpn --daemon

NetworkManager Connection:

Click on the network icon in your system tray
Look for "VPN Connections" section
Select your imported VPN configuration
The connection will be established automatically

βš™οΈ Advanced: System Service Setup

Create Systemd Service (Optional):

Copy config to system directory:
sudo cp ~/vpn-configs/london.ovpn /etc/openvpn/client/
sudo cp ~/vpn-configs/auth.txt /etc/openvpn/client/
Enable and start the service:
sudo systemctl enable openvpn-client@london
sudo systemctl start openvpn-client@london

Service Management:

Check status: sudo systemctl status openvpn-client@london
Stop service: sudo systemctl stop openvpn-client@london
View logs: sudo journalctl -u openvpn-client@london

πŸ”₯ Firewall Configuration

UFW (Ubuntu):

Allow OpenVPN traffic: sudo ufw allow 1194/udp
Enable forwarding if needed for other devices

Firewalld (Fedora/CentOS):

Allow OpenVPN service: sudo firewall-cmd --add-service=openvpn --permanent
Reload firewall: sudo firewall-cmd --reload

iptables (Manual):

Allow OpenVPN ports as needed
Configure NAT rules for routing

🌍 Server Selection Guide

Performance Recommendations:

London: Optimal for European users, excellent global connectivity
Denver: Best for North American users, central US location
Amsterdam: Great for European users, strong privacy laws

Network Optimization:

Default Port: Config files use port 1194/UDP by default
Alternative Ports Available: If blocked, servers also listen on:
UDP: 20, 123, 31482 (bypasses most firewalls)
TCP: 443, 80, 993 (works on restrictive networks)
Edit the .ovpn file to change remote server-address 1194 udp to use any alternative port
Example: remote london.cotse.net 443 tcp for HTTPS port

Testing Server Performance:

Use ping to test latency: ping london.cotse.net
Test speed after connecting: curl -s https://fast.com
Monitor bandwidth usage: vnstat -i tun0

πŸ”§ Troubleshooting

Common Linux-specific issues and solutions:

Permission Denied: Always run OpenVPN with sudo for system-level access
TUN Device Issues: Load tun module: sudo modprobe tun
DNS Resolution: Check /etc/resolv.conf after connecting
Routing Problems: Verify with: ip route show
Authentication Failed: Check username/password in auth.txt file
Connection Timeout: Verify server connectivity: telnet server-address 1194

Distribution-Specific Issues:

SELinux (RHEL/CentOS): May need to set appropriate contexts
AppArmor (Ubuntu): Check for OpenVPN profile restrictions
Network Manager Conflicts: Disable NM control of interfaces if needed
Systemd Issues: Check service logs with journalctl

Network Diagnostics:

Check interfaces: ip addr show
Monitor connection: tail -f /var/log/openvpn.log
Test external IP: curl ifconfig.me
DNS test: dig @8.8.8.8 google.com

πŸ“ž Need Help?

If you need additional assistance with OpenVPN setup on Linux or encounter any issues not covered in this guide, please contact our support team at helpdesk@codamail.com.

We're here to help ensure your VPN connection works perfectly and keeps your Linux system browsing secure and private.