Building a Ghetto WAN Emulation Network
I wanted a way to do some controlled tests of WAN acceleration products, using a production network. You can buy or rent commercial WAN emulators, but for my purposes it seemed like an improvised solution would suffice. I had a couple of Cisco 2800 routers, a switch, and an ESXi box in my lab that I could press into service, so I built a test network that looks like this:
R1 acts like the WAN router at a branch site. It has a QoS policy with a "shape average" statement on its "WAN" interface to change the bandwidth to whatever we want to test.
R2 simply NATs the test traffic onto an IP address in the production network, since I didn't feel like configuring a new production subnet just for the test.
The ESXi box is where the fun part lives: I created two vSwitches and connected one physical NIC to each. I then spun up a simple Ubuntu 12.04 VM with eth0 and eth1 connected to each of the two vSwitches, giving me a separate network connected to each Cisco router. I then enabled routing on the Linux VM and created the appropriate static routes to enable the Continue reading
