[sclug] Linux as a web-farm load-balancer

[Alex Butcher]

On Tue, 5 Aug 2008, n.a.haughton at bigfoot.com wrote:

> I want to set up a load balancer in front of a pair of WinXP webservers, to
> test some software in a web farm environment. Cash is tight, so a Linux
> solution sounds a good approach.  There are a couple of issues that I can
> see might get in the way:
>
> 1. The WinXP webservers are in an Active Directory domain. Is this an issue?

I can't think of any reason why it should be, providing that the AD domain
controller can speak to the webservers directly and vice versa.

> 2. What exactly do I have to do to set this up? I have the latest OpenSuse11
> available, for example, but am prepared to try any distro that will quickly
> and easily solve my problem.

That depends on to what extent you need to keep track of which client is
connecting to which real server. If all you're doing is serving static
content, round-robin DNS would be sufficient (perhaps combined with a short
TTL and some kind of availability test that can trigger removal of a failed
machine from the DNS pool). If you need stateful tracking of web
applications, I suspect you're out of luck without looking at things like
F5's BIG-IP product range.

> All help welcomed.
> Regards,
> Neil.

HTH,
Alex.
-- 
Alex Butcher, Bristol UK.                           PGP/GnuPG ID:0x5010dbff

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