VERITAS Storage Foundation 4.1 Oracle Administrator's Guide

Chapter 1, VERITAS Storage Foundation for Oracle
Prerelease 8 September 2005, 8:54am VERITAS File System
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The Storage Rollback facility can then be used for rolling back the file system image to the point in
time when the Storage Checkpoints were taken. In addition, Storage Checkpoints also keep track of
the block change information that enables incremental database backup at the block level.
Storage Checkpoints are writable, and can be created, mounted, and removed. Performance
enhancements in maintaining Data Storage Checkpoints (Storage Checkpoints that are complete
images of the file system) makes using the Storage Rollback feature easier and more efficient,
therefore more viable for backing up large databases.
Multi-Volume File System (MVS) Storage Checkpoint creation allows database backups without
having to shut down the database.
MVSs provide the ability to create and administer Storage Checkpoint allocation policies. Storage
Checkpoint allocation policies specify a list of volumes and the order in which to allocate Storage
Checkpoint data to them. These allocation policies can be used to control where a Storage
Checkpoint is created, allowing for separating Storage Checkpoint metadata and data onto different
volumes. They can also be used to isolate data allocated to a Storage Checkpoint from the primary
file system, which can help prevent the Storage Checkpoint from fragmenting space in the primary
file system.
For more information on understanding and using Storage Checkpoints, see “Using Storage
Checkpoints and Storage Rollback” on page 162. For more information on using VxDBA and the
GUI to manage Storage Checkpoints and Storage Rollback, see “Using the VERITAS Storage
Foundation for Oracle Graphical User Interface” on page 265 and “Using the VxDBA Utility” on
page 329.
Storage Checkpoint File System Restores
Storage Checkpoints can be used by backup and restore applications to restore either individual
files or an entire file system. Restoring from Storage Checkpoints can recover data from incorrectly
modified files, but typically cannot be used to recover from hardware damage or other file system
integrity problems. File restoration can be done using the fsckpt_restore(1M) command. See
the VERITAS File System Administrator’s Guide for more information.
Quotas
VxFS supports quotas, which allocate per-user and per-group quotas and limit the use of two
principal resources: files and data blocks. You can assign quotas for each of these resources. Each
quota consists of two limits for each resource:
◆ The hard limit represents an absolute limit on data blocks or files. A user can never exceed the
hard limit under any circumstances.
◆ The soft limit is lower than the hard limit and can be exceeded for a limited amount of time.
This allows users to temporarily exceed limits as long as they fall under those limits before the
allotted time expires.