HP ProLiant DL380 G5 DPSS, Руководство администратора

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or folder presents users with the folder or fi le history—a list of read-only, point-in-time copies of the fi le or
folder contents that users can then open and explore like any other fi le or folder. Users can view fi les
in the folder history, copy fi les from the folder history, and so on.
NFS shadow copies
UNIX users can independently access previous versions of fi les stored on NFS shares via the NFS client;
no additional software is required. Server for NFS exposes each of a share’s available shadow copies
as a pseudo-subdirectory of the share. Each of these pseudo-subdirectories is displayed in exactly the
same way as a regular subdirectory is displayed.
The name of each pseudo-subdirectory re
fl ects the creation time of the shadow copy, using the
format .@GMT-YYYY.MM.DD-HH:MM:SS. To prevent common tools from needlessly enumerating the
pseudo-subdirectories, the name of each pseudo-subdirectory begins with the dot character, thus
rendering it hidden.
The following example shows an NFS share named “NFSShare” with three shadow copies, taken on
April 27, 28, and 29 of 2003 at 4 a.m.
NFSShare
.@GMT-2003.04.27-04:00:00
.@GMT-2003.04.28-04:00:00
.@GMT-2003.04.29-04:00:00
Access to NFS shadow copy pseudo-subdirectories is governed by normal access-control mechanisms
using the permissions stored in the fi le system. Users can access only those shadow copies to which
they have read access at the time the shadow copy is taken. To prevent users from modifying shadow
copies, all pseudo-subdirectories are marked read-only, regardless of the user’s ownership or access
rights, or the permissions set on the original fi les.
Server for NFS periodically polls the system for the arrival or removal of shadow copies and updates
the root directory view accordingly. Clients then capture the updated view the next time they issue a
directory read on the root of the share.
Recovery of fi les or folders
There are three common situations that may require recovery of fi les or folders:
• Accidental fi le deletion, the most common situation
• Accidental fi le replacement, which may occur if a user selects Save instead of Save As
• File corruption
It is possible to recover from all of these scenarios by accessing shadow copies. There are separate steps
for accessing a fi le compared to accessing a folder.
Recovering a deleted fi le or folder
To recover a deleted fi le or folder within a folder:
1.
Access to the folder where the deleted fi le was stored.
2. Position the cursor over a blank space in the folder. If the cursor hovers over a fi le, that fi le is selected.
3.
Right-click, select
Properties from the bottom of the menu, and then click the Previous Versions tab.
4. Select the version of the folder that contains the fi le before it was deleted, and then click View .
5. View the folder and select the fi le or folder to recover. The view may be navigated multiple folders
deep.
6. Click Restore to restore the fi le or folder to its original location. Click Copy... to allow the placement
of the fi le or folder to a new location.
HP ProLiant DL380 G5 Storage Server
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