FedFsGlossary

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=== FedFS ===
=== FedFS ===
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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 file servers, and is consistent no matter which client it is accessed from.
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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.
=== FedFS Domain ===
=== FedFS Domain ===
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A FedFS domain is a file name space that can cross multiple shares on multiple file servers.  A FedFS domain is typically a single administrative entity, and has a name that is similar to a DNS domain name.
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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.
=== File-access client ===
=== File-access client ===
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=== Junction ===
=== Junction ===
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A junction is a link between two shared file systems.  The two shared file systems may not reside on the same server.  Junctions tie together separate shared file systems into a single FedFS domain namespace.
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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.
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A junction's ''pathname'' is the path in a file server's local namespace where the junction resides.  A junction's ''target'' is a list of locations.
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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.
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A ''location'' is a pair consisting of a file server host and the export path of a file system on that host.  Each location is a replica of the same file system data.  A target may contain one or more location.
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Currently there are two types of junctions:
Currently there are two types of junctions:
* An ''NFS basic junction'' stores location information directly in each junction
* An ''NFS basic junction'' stores location information directly in each junction
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* A ''FedFS junction'' stores location information on an LDAP server so it can be shared
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* A ''FedFS junction'' stores location information on an LDAP server so it can be shared with other fileservers
=== Junction Resolution ===
=== Junction Resolution ===
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The process where a file server converts a junction's target to data that can be used to respond to a file-access client during a referral event.
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The process where a fileserver converts the contents of a junction to data that can be used to respond to a file-access client during a referral event.
=== Location ===
=== Location ===
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Each replica of the linked-to file system is called a fileset location, or location, for shortA location is represented as an export path paired with a server name or IP address.
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A duple consisting of a fileserver host (DNS hostname or IP address) and the export path of a file system on that hostFile-access clients mount a ''location''.
=== Namespace ===
=== Namespace ===
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A filename/directory tree that a sufficiently authorized client can observe.
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A filename/directory tree that a sufficiently authorized client can access.
=== Namespace Database ===
=== Namespace Database ===
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A Namespace Database, also known as an NSDB, is the central repository of FedFS domain namespace information that is shared among all file servers in a FedFS domain.  It is accessed via the LDAP protocol.
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A Namespace Database, also known as an NSDB, is the central repository of FedFS domain namespace information that is shared among fileservers in a FedFS domain.  It is accessed via the LDAP protocol.
=== Referral ===
=== Referral ===
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A referral is a file server 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 file server 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.
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A referral is 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 ===
=== Replica ===
A replica is 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.
A replica is 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.

Revision as of 15:54, 27 November 2012

Contents

Project: fedfs-utils

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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

A domain root directory is 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

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.

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.

File-access client

A file-access client accessed 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

A fileserver 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.

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.

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 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 where a fileserver converts the contents of a junction to data that can be used to respond to a file-access client during a referral event.

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

A Namespace Database, also known as an NSDB, is the central repository of FedFS domain namespace information that is shared among fileservers in a FedFS domain. It is accessed via the LDAP protocol.

Referral

A referral is 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 replica is 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.

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