Emulab FAQ: Using the Testbed: Where do I store files needed by my experiment?
Each project has its own directory, rooted at /proj, which is available via NFS to all of the nodes in experiments running in that project. For example, when the "RON" project was created, a directory called /proj/RON was also created. This directory is owned by the project creator, and is in the unix group "RON." Its permission (mode) is 770; read/write/execute permitted by the project creator and by all of the members of the project RON, but protected against all access by people outside the RON project.
Sub-groups within a project likewise have a directory in the /groups tree. A group named "group1" in the RON project would thus have a group directory in /groups/RON/group1.
On the Utah Emulab and optionally on other sites, there is also a third per-project hierarchy, /scratch (e.g., /scratch/RON), which has more available disk space (i.e., a higher disk quota) than the corresponding /proj directory. The trade-off is that /scratch space is considered more volatile. At Utah this means that the storage is not backed up to tape and may be cleaned out with only a short advance warning.
Project members are encouraged to store any files needed by their experiments in the corresponding /proj, /groups or /scratch directories.