Andrew File System

The Andrew File System (AFS) is a distributed network file system that enables files from any AFS machine across the country to be accessed as easily as files stored locally. It is an enterprise file system designed for use in a distributed environment on multiple computing platforms. AFS allows users on various types of computers to access the same file system. To a casual UNIX user, AFS disk space looks like a regular local disk; …

…open elsewhere for writing will not get the most up-to-data version of the file. Since the server is not contacted on file open, reads, or writes for files that exist in client caches, a limited kind of availability can be maintained in the event of server unreachability. File close cannot be carried out, however, and I'm guessing that the results of attempting a file close when a server is down or unreachable are not pretty.