wiki:sppReport-1Q09

Version 2 (modified by Jon Turner, 11 years ago) (diff)

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-- Project Activities for the period 1/1/2009-3/31/2009 --

--- Upgrading of Software for System Initialization ---

The PlanetLab project made significant changes to the software that manages the booting and initialization of PlanetLab nodes. Since the SPP relies on these mechanisms as well, we have had to make some changes to our own software to accommodate the changes made by PlanetLab. As context, when a PlanetLab node comes up, it contacts PlanetLab Central (PLC) to obtain a boot image and a variety of configuration data. Since the GPEs in an SPP run the PlanetLab OS, they also attempt to contact PLC when they boot. However, the SPP is designed to look to the external world, like a single PlanetLab node, so it would be inappropriate to let the GPEs contact PLC directly. To avoid making unnecessary changes to the GPE (which would make it difficult for us to track future changes to the PlanetLab code), we have implemented a software module running on the SPP's control processor that intercepts the connections between the GPEs and PLC, hiding the internal structure of the SPP from PLC, while still getting the GPEs the information they need to complete their initialization. We have implemented and tested the changes needed to this module to allow us to stay consistent with PlanetLab.