We think of a "Site" as a unique geographic location, like a University or business address. But, not all member institutions fit this idea of a 'Site'. Some PlanetLab member institutions have multiple geographic locations, any of which can host machines dedicated to PlanetLab software. To accomodate this, we needed a way to separate the notion of physical location and the slices that are given in exchange for these sites being up. Enter the MetaSite.

It didn't seem fair to treat a MetaSite, which is the only site of a collection of related locations that can create slices, with the same policies as traditional Sites. For example, a MetaSite with four geographic locations would have registered at least two machines at each location.  As a result, the MetaSite would be contributing 8 machines in total.  If we followed just the Site policy, then just one machine of the 8 would have to go down and be unaddressed before the PI couldn't create slices anymore.

So, MetaSites have a slightly different policy. For each unique location that maintains the minimum number of nodes, the MetaSite receives 1/Nth of its total slices, where N is the total number of unique locations. So, if all unique locations are running two PlanetLab machines, then the total max_slices is available to the PI at the MetaSite.  If one site should drop below two running machines, then this only reduces the total max_slices available to the PI.

Monitor will notify the Technical Contact, followed by the PI, followed by the slice users, just as before. However, the action taken at two weeks will be to reduce the total number of slices the MetaSite can create.

At any time, if the MetaSite has fewer than 25% of its sites up, then all slices will be suspended.