Introductory Concepts regarding protecting the Loss of Data in RedHat Linux
In the best of circumstances, backups and archives will never be needed. However, data represents an investment of time and effort, and you should take measures to ensure your unique data against loss.
Hard-drive failures, software bugs, and user errors can wreak havoc, deleting or corrupting important information. In mission-critical applications, lost or inaccessible data can mean the difference between meeting deadlines and satisfying
customers or defaulting on a myriad of vital business responsibilities.
Timely, consistent, and reliable backups are an extremely important aspect of system administration. In this module, you will learn how to protect your data using appropriate backup applications and scheduling.
Additionally, you will use the file recovery facilities available in the tar utility and the restore command.
Finally, you will learn about RAID: a) what RAID is, b) the different RAID levels, and c) the differences between hardware and software RAID.
After completing this module, you will be able to:
List the kinds of tape-drive hardware supported by Linux
Recognize tape control commands
Use the tar command to back up and restore files and directories
Use the dump command to back up file systems
Use the restore command to recover file systems
List tape backup applications available from Red Hat
Explain basic concepts related to RAID
Describe RAID levels
Compare and contrast hardware and software RAID
Selecting a Backup Medium
Armed with a backup strategy in mind, it is time to select a backup medium. Several types of
backup hardware and media are available for use with Fedora and RHEL. Each type has its advantages and disadvantages.
The type of medium to choose depends largely on the amount of data you need to archive, how
long you will store backups, how often you expect to recover data from your backups, and
how much you can afford to spend.
Table 4-1 compares the most common backup media. The following sections describe how to use magnetic tape, writable DVDs, and writable CDs
as backup media.