Kb173
Emulab FAQ: Testbed Operations: What is the Emulab ethernet switch configuration?
We have not made that info available both because it is subject to change and because the impact of multiple switches should be negligible (on the order of a couple of us of latency).
But here is the current setup: there are three "experimental" switches, all cisco 6509s, interconnected with 4Gb trunk lines as:
4Gb 4Gb cisco4 <=====> cisco3 <=====> cisco1
The resource mapper takes into account the interswitch bandwidth so that it will not overload any of the interswitch links.
Currently any PC will have all its experimental interfaces connected to the same switch, though that may change in the future.
The current node assignments look like:
pc1 - pc84: cisco1 pc85 - pc128: cisco3 pc129 - pc141: cisco4 pc142 - pc168: cisco3 pc170 - pc178: cisco4 pc250 - pc251: cisco4