C/C++ version Load balancer DNS

[Chris Buxton]

> Using DNS, I want to do load balancing of client requests among my
> available servers dynamically.
> In realtime requirements, any/many servers among the configured me be
> down or overloaded.
>
> I want to have control over distribution of load to these servers. I
> want to have a common FQDN to the clients and they know only FQDN. I
> would like to have 10/20 servers handling the client requests. When
> ever a server goes down, all the requests (thousands) it was handling,
> should come to remaining available servers quickly (assume within few
> seconds).
>
> I feel we can use DNS for this purpose, but doing load balance in
> realtime?

I don't believe you will be successful at this with just DNS. The  
problem is that you want client connections switched over in case of a  
server failure. My understanding is that web browsers will not honor  
your TTL's. (This is how it was the last time I operated a production  
web server cluster, back in medieval times. I don't see why things  
would have changed.)

What you need is a load balancing solution at the HTTP level.  
Preferably more than one, such that the devices can share an IP  
together in some kind of fault-tolerant way.

Either way, if it were me, I would start my search at the F5 website.
http://www.f5.com/solutions/availability/

Chris Buxton
Professional Services
Men & Mice