Tandberg Data NAS Hardware Viking FS-1500 - Manual (Page 24)

Tandberg Data Storage & File Server Management
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3-4 Tandberg Viking Series Storage Server Administration Manual
Volumes are created out of the dynamic disks, and can be expanded on the
fly to extend over multiple dynamic disks if they are spanned volumes.
However, after a type of volume is selected, it cannot be altered. For
example, a spanning volume cannot be altered to a mirrored volume without
deleting and recreating the volume, unless it is a simple volume. Simple
volumes can be mirrored or converted to spanned volumes. Fault-tolerant
disks cannot be extended either. Therefore, selection of the volume type is
important. The same performance characteristics on numbers of reads and
writes apply when using fault-tolerant configurations, as is the case with
controller-based RAID. These volumes can also be assigned drive letters or
be mounted as mount points off existing drive letters.
The administrator should carefully consider how the volumes will be carved
up and what groups or applications will be using them. For example, putting
several storage-intensive applications or groups into the same dynamic disk
set would not be efficient. These applications or groups would be better
served by being divided up into separate dynamic disks, which could then
grow as their space requirements increased, within the allowable growth
limits.
3.1.3. File System Element
File system elements are composed of the folders and subfolders that are
created under each logical storage element (partitions, logical disks, and
volumes). Folders are used to further subdivide the available file system,
providing another level of granularity for management of the information
space. Each of these folders can contain separate permissions and share
names that can be used for network access. Folders can be created for
individual users, groups, projects, and so on.
3.1.4. File Sharing Element
The storage server supports several file sharing protocols, including
Distributed File System (DFS), Network File System (NFS), File Transfer
Protocol (FTP), Hypertext Transfer Protocol (HTTP), and Microsoft Server
Message Block (SMB). On each folder or logical storage element, different
file sharing protocols can be enabled using specific network names for
access across a network to a variety of clients. Permissions can then be
granted to those shares based on users or groups of users in each of the file
sharing protocols.
3.2. Volume Shadow Copy Service Overview
The Volume Shadow Copy Service (VSS) provides an infrastructure for
creating point-in-time snapshots (shadow copies) of volumes. VSS supports
64 shadow copies per volume.
Shadow Copies of Shared Folders resides within this infrastructure, and
helps alleviate data loss by creating shadow copies of files or folders that are
stored on network file shares at pre-determined time intervals. In essence, a
shadow copy is a previous version of the file or folder at a specific point in
time.
By using shadow copies, a storage server can maintain a set of previous
versions of all files on the selected volumes. End users access the file or
folder by using a separate client add-on program, which enables them to
view the file in Windows Explorer.