FedFsGlossary

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Revision as of 16:04, 27 November 2012

Project: fedfs-utils

Introduction

This article contains a glossary of terms related to FedFS.

Glossary

Partially derived from draft-ietf-nfsv4-federated-fs-protocol-13.

Administrative Client

A network host that performs domain administrative tasks remotely using the NSDB and ADMIN protocols.

Administrator

A user with the necessary authority to initiate administrative tasks on one or more servers in a FedFS domain.

Domain Root Directory

The top-level directory of a FedFS domain.

Federation

A collection of independently administered fileservers that are linked together by a common namespace. Also known as a FedFS Domain.

FedFS

Short for Federated File System, a set of administrative protocols and techniques for creating a file name space that can cross multiple shares on multiple fileservers, and is consistent no matter which client it is accessed from.

FedFS Domain

A file name space that can cross multiple shares on multiple fileservers. A FedFS domain is typically a single administrative entity, and has a name that is similar to a DNS domain name. Also known as a Federation.

File-access client

An entity that accesses data stored on fileservers via a standard file-access protocol such as SMB or NFS.

File-access protocol

A network filesystem access protocol such as NFSv4 or CIFS.

Fileserver

An entity that provides access to file storage via a standard file-access protocol such as NFS or SMB.

Fileset

A collection of files and directories that are considered as a single administrative unit in a FedFS domain. Each fileset may reside at a single location, or it may be replicated to several locations. All files within a fileset are descendants of one directory. Filesets do not span filesystems.

Globally Useful Name

A pathname in the FedFS domain namespace which is the same no matter which client is used to access the file.

Junction

A link between two shared file systems. These two shared file systems might not reside on the same server. Junctions tie together separate shared file systems into a single FedFS domain namespace.

A junction's pathname is the path in a fileserver's local namespace where the junction resides. A junction's target is a list of one or more locations. Each location in this list is a replica of the same file system data.

Currently there are two types of junctions:

An NFS basic junction stores location information directly in each junction
A FedFS junction stores location information on an LDAP server so it can be shared with other fileservers

Junction Resolution

The process whereby a fileserver converts the contents of a junction into a referral for a file-access client.

Location

A duple consisting of a fileserver host (DNS hostname or IP address) and the export path of a file system on that host. File-access clients mount a location.

Namespace

A filename/directory tree that a sufficiently authorized client can access.

Namespace Database

The central repository of FedFS domain namespace information that is shared among fileservers in a FedFS domain. It is accessed via the LDAP protocol. Also known as an NSDB.

Referral

A fileserver response that tells a file-access client to look elsewhere for the shared file system it wants. A referral event can occur, for example, when a fileserver reports to a client that the object the client is attempting to access has moved. The client responds by requesting a list of locations where it can find the object.

Replica

A copy of a fileset. Replicas are used to increase availability or performance. Updates to replicas appear to occur in the same order, but do not necessarily occur simultaneously.

@@ Line 29: / Line 29: @@
 === Domain Root Directory ===
-A domain root directory is the top-level directory of a FedFS domain.
+The top-level directory of a FedFS domain.
 === Federation ===
@@ Line 37: / Line 37: @@
 === FedFS ===
-FedFS is short for Federated File System.  It's a set of administrative protocols and techniques for creating a file name space that can cross multiple shares on multiple fileservers, and is consistent no matter which client it is accessed from.
+Short for Federated File System, a set of administrative protocols and techniques for creating a file name space that can cross multiple shares on multiple fileservers, and is consistent no matter which client it is accessed from.
 === FedFS Domain ===
-A FedFS domain is a file name space that can cross multiple shares on multiple fileservers.  A FedFS domain is typically a single administrative entity, and has a name that is similar to a DNS domain name.
+A file name space that can cross multiple shares on multiple fileservers.  A FedFS domain is typically a single administrative entity, and has a name that is similar to a DNS domain name.  Also known as a [[FedFsGlossary#Federation|Federation]].
 === File-access client ===
-A file-access client accessed data stored on fileservers via a standard file-access protocol such as SMB or NFS.
+An entity that accesses data stored on fileservers via a standard file-access protocol such as SMB or NFS.
 === File-access protocol ===
@@ Line 53: / Line 53: @@
 === Fileserver ===
-A fileserver provides access to file storage via a standard file-access protocol such as NFS or SMB.
+An entity that provides access to file storage via a standard file-access protocol such as NFS or SMB.
 === Fileset ===
-A fileset is a collection of files and directories that are considered as a single administrative unit in a FedFS domain.  Each fileset may reside at a single location, or it may be replicated to several locations.  All files within a fileset are descendants of one directory.  Filesets do not span filesystems.
+A collection of files and directories that are considered as a single administrative unit in a FedFS domain.  Each fileset may reside at a single location, or it may be replicated to several locations.  All files within a fileset are descendants of one directory.  Filesets do not span filesystems.
 === Globally Useful Name ===
-A Globally Useful Name is a pathname in the FedFS domain namespace which is the same no matter which client is used to access the file.
+A pathname in the FedFS domain namespace which is the same no matter which client is used to access the file.
 === Junction ===
-A junction is a link between two shared file systems.  These two shared file systems might not reside on the same server.  Junctions tie together separate shared file systems into a single FedFS domain namespace.
+A link between two shared file systems.  These two shared file systems might not reside on the same server.  Junctions tie together separate shared file systems into a single FedFS domain namespace.
-A junction's ''pathname'' is the path in a fileserver's local namespace where the junction resides.  A junction's ''target'' is a list of one or more ''locations''.  Each location in this list is a replica of the same file system data.
+A junction's ''pathname'' is the path in a fileserver's local namespace where the junction resides.  A junction's ''target'' is a list of one or more [[FedFsGlossary#Location|locations]].  Each location in this list is a replica of the same file system data.
 Currently there are two types of junctions: