The standard
file system backup and restore facilities that native operating systems
provide are generally inadequate for backing up and restoring SPD
Server tables. SPD Server tables can be enormous in size, surpassing
the file size limits maintained by some operating environments. SPD
Server is also dependent on the operation environment's ability to
detect a modification to a table, such as an add, delete, or change
of a record. A change in a table is normally a signal to ensure that
the newly modified file is backed up.
When
a standard utility subsequently performs an incremental backup, it
processes the file change by backing up the entire table. If the table
is very large, the backup time can be lengthy. In addition, the processing
can consume considerable machine resources. For this reason, administrators
frequently struggle with a dilemma: are incremental backups of large
tables worth the resources they consume?
The Scalable
Performance Data Server backup and restore utilities alleviate these
problems because they 'sense' the table data. The backup utility is
capable of a real incremental backup. That is, instead of backing
up the entire table, the utility backs up only the records that changed
after the previous table backup date. Further, if a later restore
of the table becomes necessary, the restore utility can incrementally
restore the table to its last backup state.
By backing
up only the changed records, SPD Server conserves valuable system
resources. This, in turn, encourages more frequent backups. The increased
frequency realizes the ultimate goal of the utilities: to minimize
possible loss or corruption of an SPD Server table for whatever reason.
Moreover, the software gives you a choice for periodic full backups:
you can use the SPD Server full backup and restore capabilities or
you can use your system's full backup and restore facilities.
In summary,
the SPD Server incremental backup and restore facilities, used with
the full backup and restore capabilities of either SPD Server or your
system, can furnish comprehensive backup and restore capabilities.
The SPD
Server backup and restore utilities include:
-
spdsbkup Performs
incremental or full backups of SPD Server tables, storing the information
in an SPD Server backup data file.
-
spdsrstr Performs
incremental or full restores of SPD Server tables using the SPD Server
backup data file created by the utility.