User Guide
12 Novell Storage Services Administration Guide
Novell Storage Services Administration Guide
103-000141-001
August 30, 2001
Novell Confidential
Manual 99a38 July 17, 2001
Retain Previously Saved Files (Snapshot)
The File Snapshot feature allows your backup utility to keep a consistent copy
of all files. This is done by having the file system keep an original copy of all
open files. For example, when your system backs up or crashes at a time when
you are modifying a file, the backup could contain both old and new data.
Snapshot captures the most recent closed copy of the file. This way, if you lose
data between the backup cycles, you still have a solid copy of the previously
saved file.
Transaction Tracking System (TTS)
Transaction Tracking System
TM
protects database applications by backing out
transactions that are incomplete due to a system failure. TTS
TM
can be
available on either all traditional or all NSS logical volumes. It cannot be
available on all volumes if you use both types of volumes. If your system uses
both traditional and logical volumes, by default it can only work on traditional
volumes. If you want to use it on logical volumes on a system that has both,
you must enter DISABLE TTS on the AUTOEXEC.NCF then enable the
feature on each logical volume you want it on. Unlike traditional volumes,
TTS does not apply to logical volumes by default. To enable it on logical
volumes, enter nss/transaction=volname.
Review the Modified File List
The Modified File List is a list of files that changed since the previous backup.
The backup utility accesses this list instead of searching the entire file system.
Use Clustering Feature
Some storage devices exist in a storage area network (SAN). These devices
can be shared by multiple servers in a cluster. For more information about
clustering, see Novell Cluster Services Overview and Installation.
Enable File Compression
NSS supports file compression. This lets you decide whether to compress the
files in your volumes to create additional space. Once you enable file
compression, you cannot turn it off without recreating the volumes.