Each member site of PlanetLab receives some Slices in exchange for two machines running the PlanetLab node software. For all sorts of reasons, the machine can stop: maybe due to lost power, kernel crashes, or network disconnection. Who knows. To follow what's going on, Monitor periodically looks at the status of the machines at your site and makes a note of it.

After a machine is down for longer than one week, Monitor will send a message to the Technical Contact at your site. System administrators are busy, busy people. We totally get that. And their first priority may not be responding to a maintenance request for a PlanetLab machine.

However, if we don't hear back from someone acknowledging that they'll look into the problem and the total number of running machines at your site drops below two for longer than two weeks, then we will contact the PI at your site and slice creation is turned off. As a result, no new slices can be created, but the existing slices will continue running on PlanetLab uninterrupted.

If we still don't hear back from either the PI or Technical Contact after three weeks, then all slice users will be emailed and all slices on PlanetLab will be disabled. The idea is that anyone actually benefitting from PlanetLab will have some added incentive to get the machines back up and running. If we continue to not hear from anyone, then periodic emails will be sent after this to remind everyone about the situation.