Okay back to network topology then. How does hadoop determine a 'rack' of machines?
Currently we have everything on a single VLAN, with the DFS master being the gateway back to our main VLAN.
We were hoping to group subsets of machines on a local switch, and optionally have each machine have a connection to the vlan which is the backbone of the entire cluster.
In terms of more exotic situations we were discussing having 4 NIC's 1 for the local subset, 1 for a pair of local subsets, 1 for another pair of local subsets, 1 for the backbone.
Our job mix is totally varied from IO bound to CPU bound -- Jason Venner Attributor - Publish with Confidence <http://www.attributor.com/> Attributor is hiring Hadoop Wranglers, contact if interested
