openvpn.md

OpenVPN Package Availability & Upgrade Options (Ubuntu & CentOS Stream 9)

1. Current OpenVPN Versions

Distribution	Repo	Version	Release Date
Ubuntu 22.04 (Jammy)	Main	2.5.9	16/02/2023
	Updates	2.5.11	18/07/2024
	Backports	2.6.12	18/07/2024
Ubuntu 24.04 (Noble)	Main	2.6.14	02/04/2025
	Updates	2.6.14	02/04/2025
	Backports	N/A	—
CentOS Stream 9	EPEL	2.5.11	18/07/2024
Upstream OpenVPN (Latest Stable)	—	2.6.19	04/02/2026
Upstream OpenVPN (Previous Stable)	—	2.6.17	28/11/2025

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2. Getting the Latest OpenVPN on Ubuntu

Ubuntu LTS releases often lag behind upstream OpenVPN development.
To install the latest OpenVPN packages, including DCO‑enabled builds:

Official Upstream APT Repository

https://build.openvpn.net

This repository provides:

• The newest OpenVPN releases (2.6.x and 2.7 prereleases)

• Updated DCO kernel modules

• Consistent builds across Ubuntu versions

This is the recommended method when you need:

• Maximum performance

• DCO support

• Feature parity across multiple systems

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3. Getting the Latest OpenVPN on CentOS Stream 9

CentOS Stream 9 does not include OpenVPN in its official repositories.

The only official package (2.5.11) is provided via EPEL, which is outdated compared to upstream.

To install the latest OpenVPN releases, use the Fedora COPR repository:

Fedora COPR (OpenVPN)

• Provides modern OpenVPN 2.6.x builds

• Includes DCO kernel module packages

• Only reliable source for up‑to‑date OpenVPN on EL9 platforms

This is essential if you need:

• DCO support

• Latest security fixes

• Performance improvements introduced after 2.5.x

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4. OpenVPN DCO (Data Channel Offload) — What It Is and Why It Matters

OpenVPN 2.6 introduced DCO, a major architectural improvement.

What DCO Does

• Moves the encrypted data path from user space into the Linux kernel

• Reduces context switching overhead

• Improves throughput significantly

• Lowers CPU usage

• Enables high‑speed tunnels on modern hardware

Important Notes

• DCO requires an additional kernel module.

• The module changed names between OpenVPN 2.6 and 2.7 due to major redesigns.

• Both modules can be installed side‑by‑side.

• OpenVPN still works without DCO, but performance is lower.

Why DCO Is Important

If you're running:

• High‑bandwidth VPN tunnels

• Multi‑client VPN servers

• Low‑power devices (ARM SBCs, VPS instances)

…DCO can provide a substantial performance boost.

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5. Summary

• Ubuntu and CentOS Stream 9 ship older OpenVPN versions by default.

• To run the latest OpenVPN (2.6.17+ or 2.6.19), use upstream repositories:

  • Ubuntu: https://build.openvpn.net

  • CentOS Stream 9: Fedora COPR OpenVPN repo

• DCO support requires installing the matching kernel module.

• Using upstream packages ensures consistent features, performance, and security across all systems.