How to take off load from a server with Round Robin Loadbalancing
The nameserver configuration to push users randomly to server A or server B, called round robin, is a very cost effective and easy way to cope with growth.
If you can copy your pages to 2 (or more) different webservers, which could both serve the same domain, you are half way there.
Please take a look here for a detailed howto to setup your round robin configuration.
If you have done that and users are pushed randomly to server A or B, you have to make sure, your application can work in that stateless mode.
PHP based services do use “sessions” most of the time to handle data connected to a registered user. We have configured our server to handle all sessions in a seperate database, which we could connec to to over the internal network.
For us, a perfect growing environment:
2 webservers, 1 database server and 1 storage device, which can be accessed via NFS.
In that setup, you may “plug in” more webservers any time and handle a growing audience of users, up to 60,000 unique visits a day.
February 1st, 2006 at 10:21 am
[...] I have written a short article about simple load balancing a few weeks ago and wanted to pick that topic up once more, because people keep contacting me about that. [...]