Customer Questions:

Since we are doing our load-balancing via dns servers, what happens when dns is cached across the internet?

Yes the Internet (i.e. DNS servers on the Internet) does cache DNS information.

To be more specific, the Edge router provides each server address to the various DNS servers and clients that request them. Each time a request is made the addresses are provided in a different order, and each DNS request times out within five minutes. Therefore there is a constant change in which WAN interface is used for the inbound traffic, and thus the bandwidth on each interface is "load-balanced". Additionally, various administrative parameters can be changed in order to adjust how the load-balancing is affected.