Viability of nginx instead of hardware load balancer?

[Barry Abrahamson]

On Sep 17, 2009, at 5:49 AM, John Moore wrote:

> It certainly does, thanks! Could I trouble you to explain a little  
> more about your use of Wackamole and Spread? I've not used either of  
> them before.

There is a How-to here:

http://www.howtoforge.com/setting-up-a-high-availability-load-balancer-with-haproxy-wackamole-spread-on-debian-etch-p2

You are just using nginx instead of HAProxy, but the Wackamole and  
Spread portion still applies.

Scalable Internet Architectures ( http://www.amazon.com/Scalable-Internet-Architectures-Theo-Schlossnagle/dp/067232699X 
  ) also has a section on how this works.

> Also, is there any reason why a hosting company would have problems  
> with such a setup (i.e., this won't be running in our hardware on  
> our premises, but we have full control of Linux servers).

Yes, you have to be a little careful here and ask questions up front.   
A lot of hosting companies segment their switches such that each port  
is it's own VLAN which means you can't "float" IPs between ports which  
is what you need for this to work.  If you tell your hosting company  
what you are trying to do and tell them that you need to be able to  
have IPs which are programmatically moved between switch ports they  
should be able to tell you if this is possible or not.  Some hosts may  
require you have some sort of "private rack" or other upgrade to make  
this possible.

Barry

--
Barry Abrahamson | Systems Wrangler | Automattic
Blog: http://barry.wordpress.com