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LibreSwan

by LibreSwan

Free plan LinuxSelf-hosted

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LibreSwan's own site

What LibreSwan is

LibreSwan is free software for site-to-site networking through the standardized IPsec VPN protocol and Internet Key Exchange. It supports IKE versions 1 and 2; the documentation describes IKEv1 as deprecated and strongly recommends migration to IKEv2. The software runs on Linux, FreeBSD, NetBSD, and OpenBSD, although OpenBSD users need to build it from source. On Linux, it uses the built-in XFRM IPsec stack and integrates with the operating system's init system. Supported extensions include X.509 certificates and NAT traversal. Authentication can use X.509 certificates, raw private keys, or preshared secrets, with NSS handling cryptographic storage. Configuration guides cover AWS, Microsoft Azure, Oracle Cloud, OpenStack, and Cisco ASA or VPN3000 connections. Documented packages include Alpine, Arch, CentOS, Debian, Fedora, FreeBSD, Mint, Oracle Linux, Red Hat Enterprise Linux, and Ubuntu. The project traces its history to 1997, is actively developed, and is mostly licensed under GPLv2. Volunteer and commercial support are available.

Who it suits

LibreSwan suits administrators building VPN connections on supported Unix-like systems. It is relevant when site-to-site IPsec, cloud interoperation, and certificate or preshared-secret authentication are required.

What it does well

  • Free IPsec and IKE VPN implementation
  • Supports Linux, FreeBSD, NetBSD, and OpenBSD
  • X.509 and NAT traversal extensions
  • Guides cover major cloud platforms
  • Certificate, key, and preshared authentication

What to know first

  • IKEv1 is deprecated
  • OpenBSD requires building from source
  • Volunteer support response times may vary
  • Most code uses GPLv2, with other licenses

Plans

PlanBilled and limitsPrice
LibreSwanFree software implementation of IPsec/IKE VPN · GPLv2Free

As libreswan.org lists them, read 11 Oct 2026. The maker's own page has the final word.

Verdict

LibreSwan provides a free, multi-platform implementation of IPsec VPN and IKE with broad authentication and deployment documentation. Users should plan around the project's IKEv2 recommendation and the source-build requirement on OpenBSD.

Facts from LibreSwan's own pages

Access model
vpn · libreswan.org, 22 Sept 2026
Authentication and crypto
LibreSwan uses NSS for cryptographic storage and supports X.509 certificates, raw private keys, and preshared secrets. · libreswan.org, 11 Oct 2026
Cloud and interoperability
Project configuration guides cover AWS, Microsoft Azure, Oracle Cloud, OpenStack, and Cisco ASA or VPN3000 connections. · libreswan.org, 11 Oct 2026
Commercial support
The project lists commercial support from core developers and notes that users of commercial Linux vendors may already have support coverage. · github.com, 11 Oct 2026
Community support
Free volunteer support is available through mailing lists, the Libera.Chat #libreswan channel, and the GitHub bug database, and response times may vary. · github.com, 11 Oct 2026
Core features
The project documentation lists support for X.509 certificates and NAT traversal among its IPsec extensions. · libreswan.github.io, 11 Oct 2026
Deployment
LibreSwan runs on Linux, FreeBSD, NetBSD, and OpenBSD; the project says OpenBSD users need to build it from source. · libreswan.github.io, 11 Oct 2026
Distribution packages
The documentation lists prebuilt packages for Alpine, Arch, CentOS, Debian, Fedora, FreeBSD, Mint, Oracle Linux, Red Hat Enterprise Linux, and Ubuntu. · libreswan.github.io, 11 Oct 2026
Founded
1997 · libreswan.org, 28 Sept 2026
Free plan
Yes · libreswan.org, 22 Sept 2026
License
The project says the bulk of LibreSwan is licensed under GNU General Public License version 2, with some smaller parts under different licenses. · libreswan.github.io, 11 Oct 2026
Linux integration
On Linux, LibreSwan uses the built-in XFRM IPsec stack and integrates with the operating system's init system. · libreswan.org, 11 Oct 2026
Project history
The project says it has been under active development for over 20 years and traces its history to The FreeS/WAN Project, founded in 1997. · libreswan.org, 11 Oct 2026
Protocols
It supports IKE versions 1 and 2, with IKEv1 described in its manual as deprecated and migration to IKEv2 strongly recommended. · libreswan.org, 11 Oct 2026
Purpose
LibreSwan is free software that implements the standardized IPsec VPN protocol using Internet Key Exchange (IKE). · libreswan.org, 11 Oct 2026
Security reporting
Security issues can be reported to the project by email, including encrypted email using its OpenPGP key, and the team typically responds within a few days. · libreswan.org, 11 Oct 2026
Site-to-site networking
Yes · libreswan.org, 22 Sept 2026
Supported platforms
Linux,FreeBSD,NetBSD,OpenBSD · libreswan.org, 22 Sept 2026

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