Web Application Redundancy

[RichardParry]

Hi All,

I have developed a large business web application system, that's built in ASP (classic) with a SQL Server database back-end. I need to make the applicatin as redundant as possible, but within a budget.

I have already got dual SQL servers installed in a cluster for redundancy, but only a single web server running 2k3 Web Edition. I want to deploy another 2x servers, but need to somehow failover on to the other systems. Setting up another few servers and getting this to work would be quite simple, but I need to maintain a single code-base and not have to update code on multiple servers. Is there a way to somehow within Windows automatically replicate content within folders etc for redundancy?

Also, what is the best way to load-balance/failover between the systems? I could purchase a load balancer appliance, but these are expensive. Is there a better way to handle load-balancing/failover without an expensive load balancer or using Round Robin DNS? The latter is easy peasy, but is it the best way forward?

Thanx! Richard

 

[lgarner]

The best way is with a redundant load balancer. They range from free (you provide the hardware, of course) to thousands of dollars. Typically, you get what you pay for in management and ease of configuration, but I've used the free version in production and it's very good. I've also use F5 and would choose it if I have the money. If the site is worth duplicating, it's probably worth a good load balancer.

Round Robin DNS could work, but will affect your site's performance. Windows clustering might work, but I haven't used it and don't know how far it scales.

Windows doesn't have replication tools that I know of for this, but you can add rsync or Robocopy and keep all servers updated from one master.