Package: sup (20091019-1 and others)

Software Upgrade Protocol implementation

The SUP System is a set of programs developed by Carnegie Mellon University that provide for collections of files to be maintained in identical versions across a number of machines. These programs are:

SUP: The "client" program, run by users or system maintainers, which initiates the upgrade activity on a machine requesting the latest version of a collection of files. SUP will normally be run as a daemon, firing up once each night (week, etc.) to upgrade the specified file collections.

SUPFILESRV: The "file server" program, a daemon that is run by the system maintainer to service requests for files initiated by client SUP programs. The file server runs on every machine used as a "repository" of distributable versions of files. It runs continuously and listens for network connection requests by individual client processes; for each individual client request, a process is forked to service that request.

SUPSCAN: The "file scanner" program, that may optionally be run periodically to speed up execution of the file server. It pre-compiles a list of files on the file system that match the specifications for a given file collection so that the file server need not do this during each upgrade of that collection. The file scanner is normally used daily for very large file collections that are upgraded by many clients each day; it is not so useful for small file collections or for those that are upgraded by only a few client machines per day.

Tags: System Administration: Clustering, File Distribution, User Interface: Daemon, Networking: Client, Server, Service, Role: Program, Purpose: Synchronisation