HAProxy

Last updated
Original author Willy Tarreau
Initial releaseDecember 16, 2001;23 years ago (2001-12-16)
Stable release
3.2.0  OOjs UI icon edit-ltr-progressive.svg / 28 May 2025
Repository
Written in C
Operating system Linux, FreeBSD, OpenBSD, Solaris (8/9/10), AIX (5.1–5.3), macOS, Cygwin
License GNU General Public License Version 2
Website www.haproxy.org   OOjs UI icon edit-ltr-progressive.svg

HAProxy is a free and open source software that provides a high availability load balancer and proxy (forward proxy, [1] reverse proxy) for TCP and HTTP-based applications that spreads requests across multiple servers. [2] It is written in C [3] and has a reputation for being fast and efficient (in terms of processor and memory usage). [4]

Contents

HAProxy is used by a number of high-profile websites including GoDaddy, GitHub, Bitbucket, [5] Stack Overflow, [6] Reddit, Slack, [7] Speedtest.net, Tumblr, Twitter [8] [9] and Tuenti [10] and is used in the OpsWorks product from Amazon Web Services. [11]

History

HAProxy was written in 2000 [12] by Willy Tarreau, [13] a core contributor to the Linux kernel, [14] who still maintains the project.

In 2013, the company HAProxy Technologies, LLC was created.[ citation needed ] The company provides a commercial offering, HAProxy Enterprise and appliance-based application-delivery controllers named ALOHA.

Features

HAProxy has the following features:

HAProxy Community vs HAProxy Enterprise

HAProxy Enterprise Edition is an enterprise-class version of HAProxy that includes enterprise suite of add-ons, expert support, and professional services. It has some features backported from the HAProxy development branch. [19]

ALOHA

HAProxy Technologies’ ALOHA is a plug-and-play load-balancing appliance that can be deployed in any environment. ALOHA provides a graphical interface and a templating system that can be used to deploy and configure the appliance. [20]

Versions

HAProxy has had the following version releases: [21]

VersionRelease dateEnd of life
Unsupported: 1.02001-12-162001-12-30
Unsupported: 1.12002-03-102006-01-29
Unsupported: 1.22003-11-092011-08-06
Unsupported: 1.32006-06-292016-03-14
Unsupported: 1.42010-02-262018-02-08
Unsupported: 1.52014-06-192020-01-10
Unsupported: 1.62015-10-132020-Q4
Unsupported: 1.72016-11-252021-Q4
Unsupported: 1.82017-11-262022-Q4
Unsupported: 1.92018-12-192020-Q2
Unsupported: 2.02019-06-162024-Q2
Unsupported: 2.12019-11-252021-Q1
Supported: 2.2 LTS2020-07-072025-Q2 (critical fixes only)
Unsupported: 2.32020-11-052022-Q1
Supported: 2.4 LTS2021-05-142026-Q2 (critical fixes only)
Unsupported: 2.52021-11-232023-Q1
Supported: 2.6 LTS2022-05-312027-Q2
Unsupported: 2.72022-12-012024-Q1
Supported: 2.8 LTS2023-05-312028-Q2
Unsupported: 2.92023-12-052025-Q1
Supported: 3.0 LTS2024-05-292029-Q2
Supported: 3.12024-11-262026-Q1
Latest version:3.2 LTS2025-05-282030-Q2
Legend:
Unsupported
Supported
Latest version
Future version

Performance

Servers equipped with 6 to 8 cores generally achieve between 200,000 and 500,000 requests per second, and have no trouble saturating a 25 Gbit/s connection under Linux. [22] 64-core ARM servers were shown to reach 2 million requests per second and 100 Gbit/s. [23]

Similar software

See also

References

  1. "HAProxy as Forward Proxy".
  2. "MySQL Load Balancing with HAProxy". Severalnines AB. 2011. Retrieved 19 February 2013.
  3. "HAProxy on Freecode" . Retrieved 5 April 2013.
  4. Tsoukalos, M. "HAProxy: TCP load balancer". Linux Format. 2017;(224):76-79. Retrieved July 25, 2025.
  5. "The inner guts of Bitbucket". YouTube . 24 July 2014. Retrieved 26 February 2015.
  6. "What it takes to run Stack Overflow" . Retrieved 22 November 2013.
  7. "All Hands on Deck". Slack Engineering. 29 June 2020. Retrieved 2020-07-07.
  8. "HAProxy: they use it!" . Retrieved 5 April 2013.
  9. "List of sites using HAProxy". Archived from the original on 10 June 2013. Retrieved 5 April 2013.
  10. "Tuenti+WebRTC (Voip2day 2014)".
  11. "HAProxy layer - AWS Opsworks" . Retrieved 5 April 2013.
  12. "HAProxy: design choices and history" . Retrieved 5 April 2013.
  13. "Willy Tarreau: About me" . Retrieved 5 April 2013.
  14. "LKML: Willy Tarreau: [ANNOUNCE] Linux 2.4.37.11" . Retrieved 5 April 2013.
  15. Corbett, Daniel (2018-12-19). "HAProxy 1.9 Has Arrived". HAProxy Technologies. Retrieved 2019-01-22.
  16. Ramirez, Nick (2022-05-31). "Announcing HAProxy 2.6". HAProxy Technologies. Retrieved 2023-07-30.
  17. Mhedhbi, Moemen (2018-05-31). "Hitless Reloads / Hot Restarts with HAProxy!". HAProxy Technologies. Retrieved 2019-01-22.
  18. Ramirez, Nick (2019-01-16). "HAProxy 1.9.2 Adds gRPC Support". HAProxy Technologies. Retrieved 2019-01-22.
  19. "HAProxy Technologies Announces Improvements to Performance, Management, and Security for Enterprises" (Press release). 2 May 2018. Retrieved 23 Oct 2018.
  20. "ALOHA Hardware Appliance Application Delivery Controller" . Retrieved 23 Oct 2018.
  21. "HAProxy" . Retrieved 15 December 2022.
  22. haproxy.org#plat
  23. www.haproxy.com/blog/haproxy-forwards-over-2-million-http-requests-per-second-on-a-single-aws-arm-instance/