This title builds upon VMS File System Internals by Kirby McCoy to augment areas where the file system has changed and incorporates discussion where new file system features have been added. The book explores and documents the internal workings of the OpenVMS File system. It also covers aspects of the file system related to OpenVMS operation. and in memory, and the algorithms used by the file system. It explores the caching algorithms and the mechanisms used to coordinate access to the file system's caches and components both in a single system configuration and, more importantly, in the OpenVMS cluster environment. update addresses additional features which have come of age with Alpha such as the ODS5 file system, caching techniques like the extended file cache (XFC) and, provided there are no barriers to accessing the information, some future plans for the OpenVMS File system. Some discussion is included pertaining to ODS3 and ODS4 - designations referring to CDrom based file systems - and how OpenVMS treats them to present a consistent view of disparate files systems to an OpenVMS user.