Active/Active datacenters with CSS

branfarm1 · ‎07-15-2008

This is going to sound pretty general at first, but is there any way to do active/active balancing between two datacenters using Cisco CSS's?

let me explain that a bit further.

In my case, I'm not necessarily interested in having clients load-balanced between two datacenters as a whole, but more like having members of a load-balanced service group being located in two different datacenters.

For example, I have two Datacenters, DC1 an DC2, each with a public IP for a certain TCP application. The public IP's are the front end addresses for a load-balanced cluster of application servers. In the past, we've had it so that each datacenter was completely seperate -- each public IP went to a group of servers within that datacenter. I want to change it though so that each public IP is the front end for a load-balanced group of servers that are located in both datacenters. Currently, each datacenter is it's own /24 subnet.

I do realize that it might not be possible to adapt the existing infrastructure to support inter-datacenter load-balancing, in that case, can anybody point me in the right direction to build a new infrastructure that can support that?

Thanks in advance for the help.

Gilles Dufour · ‎07-16-2008

This is possible.

You can configure the remote servers as part of your loadbalancing content rule.

You just need to make sure the servers response will go back to the CSS.

This probably require configuring client nat.

Gilles.

branfarm1 · ‎07-16-2008

Thanks Gilles. Just to clarify, your saying I need to NAT the incoming client connections to something unique per datacenter, right? So, for example, incoming connections in DC1 will be NAT'd to 10.250.0.0/16, and incoming connections in DC2 will be NAT'd to 10.240.0.0/16. Then I configure routing back through the CSS for those ranges?

Thanks again,

--Brandon

branfarm1 · ‎07-24-2008

Also, how does something like the GSS fit into a scenario like this?