Backup Software: Buy Versus Build - Red Hat ENTERPRISE LINUX 3 - INTRODUCTION TO SYSTEM ADMINISTRATION Administration Manual

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Application Software
This data changes whenever applications are installed, upgraded, or removed.
Application Data
This data changes as frequently as the associated applications are run. Depending on the specific
application and your organization, this could mean that changes take place second-by-second or
once at the end of each fiscal year.
User Data
This data changes according to the usage patterns of your user community. In most organizations,
this means that changes take place all the time.
Based on these categories (and any additional ones that are specific to your organization), you should
have a pretty good idea concerning the nature of the backups that are needed to protect your data.
Note
You should keep in mind that most backup software deals with data on a directory or file system level.
In other words, your system's directory structure plays a part in how backups will be performed. This
is another reason why it is always a good idea to carefully consider the best directory structure for a
new system and group files and directories according to their anticipated usage.

8.2.2. Backup Software: Buy Versus Build

In order to perform backups, it is first necessary to have the proper software. This software must not
only be able to perform the basic task of making copies of bits onto backup media, it must also inter-
face cleanly with your organization's personnel and business needs. Some of the features to consider
when reviewing backup software include:
Schedules backups to run at the proper time
•
Manages the location, rotation, and usage of backup media
•
Works with operators (and/or robotic media changers) to ensure that the proper media is available
•
Assists operators in locating the media containing a specific backup of a given file
•
As you can see, a real-world backup solution entails much more than just scribbling bits onto your
backup media.
Most system administrators at this point look at one of two solutions:
Purchase a commercially-developed solution
•
Create an in-house developed backup system from scratch (possibly integrating one or more open
•
source technologies)
Each approach has its good and bad points. Given the complexity of the task, an in-house solution is
not likely to handle some aspects (such as media management, or have comprehensive documentation
and technical support) very well. However, for some organizations, this might not be a shortcoming.
A commercially-developed solution is more likely to be highly functional, but may also be overly-
complex for the organization's present needs. That said, the complexity might make it possible to
stick with one solution even as the organization grows.
Chapter 8. Planning for Disaster