The sys admin's daily grind: HAProxy

Balancing Stuntman

Article from Issue 104/2009
Author(s):

Charly's candidate today is the HAProxy load balancer, which not only distributes the load between servers, but also helps admins overcome their fears of lengthy configuration files.

Linux has no lack of free load balancers. Previously, I talked about Pen [1], which you can set up in a couple of minutes, and Pound [2], which is world famous. However, the high flyer in the balancer scene, HAProxy [3], has thus far led a fairly secluded life as an "Unknown Stuntman" [4]. The HAProxy balancer can handle any aspect of the proxy business – yet nobody has heard of it. The program's author, Willy Tarreau, has successfully demonstrated his competence as the maintainer of the 2.4 kernel, but it doesn't look as if userspace software users are interested in taking his offerings.

HAProxy uses a single thread – multithreading is for the timid. Tarreau's single-thread approach offers the decisive benefits of low overhead and high speed but requires meticulous care on the part of the developer. The single thread can go down because of a single error – a memory leak or a race condition, for example – and then the stuntman takes a tumble without a safety net.

[...]

Use Express-Checkout link below to read the full article (PDF).

Buy Linux Magazine

SINGLE ISSUES
Print Issues
Digital Issues
 
SUBSCRIPTIONS
Print Subs
Digisubs
 
TABLET & SMARTPHONE APPS
Get it on Google Play

US / Canada

Get it on Google Play

UK / Australia

Related content

  • Charly’s Column: Cluster SSH

    Charly doesn’t relish the idea of searching through the logfiles of a dozen proxy servers when page requests fail. Now that he has deployed Cluster SSH, he can pull the strings on many machines at the same time.

    more »
  • Transcoding with CasaOS

    You can set up an automatic transcoding tool with CasaOS, HandBrake, FileBrowser, and HAProxy, to transcode your video library with ease. We show you how to get started.

    more »
  • Social Aid

    Fortunately, Facebook is not the only place you can chat: When sys admin columnist Charly Kühnast visits the web chat center Reddit, he often goes without a web browser and uses the RTV tool, which can even display photos and videos on plain text consoles.

    more »
  • Charly's Column – Mi Flora

    Columnist Charly Kühnast recently attached Mi Flora humidity sensors to his potted plants. At first, they only transmitted junk on Bluetooth, but armed with the right tools and a Rasp Pi, Charly now reaps a rich harvest of data.

    more »
  • Charly's Column – Go Access

    Just as a craftsman is unlikely to purchase a new angle grinder every month, sys admins are unlikely to change constantly their tried and trusted tools. Columnist Charly Kühnast ditches this conservative philosophy this month, lured by the charms of a new logfile tool.

    more »
comments powered by Disqus
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters

Support Our Work

Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.

Learn More

News

Tag Cloud

Administration Community Events Hardware Linux Linux Pro Magazine Mobile Programming Security Software Ubuntu Web Development Windows free software open source