Node usage, particularly on the d710s, will be high for the next week due to a conference deadline.
The new Emulab reservation system, and its incomplete integration with the old Emulab UI, may be leading you to believe that there are nodes free when there really aren't.
If you see a message like:
*** Resource reservation violation: 1 nodes of type d710 requested, but
only 0 available because of existing resource reservations to other
you should believe it.
To get a more accurate accounting of available nodes, you should go through the new "portal" interface and look at the new Cluster status page and look at "Emulab Totals".
For information about the reservation system, see the Resource Reservations section of the new manual. Use the Reserve Nodes menu item to make a reservation.
For information about switching to the new portal interface to Emulab, see the Transitioning section of the manual.