Use whiteball for free nodes since they otherwise would look down (no isalive reported from pxeboot kernel when node is free).
Use whiteball for free nodes since they otherwise would look down (no
isalive reported from pxeboot kernel when node is free).

nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome