To achieve Internet loadbalance and redundancy, we currently connect to SBC (T1/Frame Relay) and TimeWarner (Cable) for Internet access. Between the edge routers (2600/2500) and our ASA firewall, we position a 3rd router as loadbalancer using CEF, RIP2, PBR (for outgoing) and a pair of default routes. At the cost of three old routers, it has worked very well for us. We do, however, have the following two limitations:
1. Our CEF loadbalance is connection based (can't use packet-based because we only have a class-C space, not big enough to be on the internet routing table). Therefore, we cannot loadbalance according to available bandwidth on both uplinks.
2. The dynamic routing setup only detects immediate link failures. It cannot detect performance degration on a particular link or a remote upstream failure. When an ISP has problems, our users experience random Internet problems because they may be redirected to go through the ISP with problems.
Does anyone have any experience with a low-cost solution, like Linksys RV-082, Xincom XC-DPG502, and Zyxel Zywall 70?
As to No.2, I am thinking about writing a script for our net monitoring software to test for link speed to certain popular web sites and shut down an Internet link if it gets too slow.
But I'd don't want to "reinvent the wheel" if there is a low-cost solution out there already.