Microsoft Word Hardware Reconfiguration Methodology V final2

Methodology I - backup and restoration

1. Objective

The objective of this section is to examine in detail the various issues that must be understood before attempting to undertake the task of preparing and creating full system backups. Backups are vital to restoring the system to an operational state should any system changes fail. Failure can occur during laboratory tests, migrations, reconfiguration, updates, upgrades, or manual system maintenance. The importance of having a laboratory for testing purposes cannot be overemphasized. In this test environment various backup and restoration procedures can be examined to ensure the applicability and usefulness of a given backup-restoration scheme, as well as ensure data integrity before proceeding with Part II.

2. Backup considerations

1. Plan development

A plan should be developed prior to performing any backup of the computer systems and their filesystems. This plan should take into account the various facets necessary for a successful backup as are examined in the following sections. A backup plan will be the result of a methodological analysis that is a synthesis of the organization’s operational policy and requirements that also includes the computers’ operating system capabilities and requirements. In addition, a backup plan must be both flexible and adaptable, as contextual changes that are likely to occur must accommodate for unforeseen errors and mistakes. These contentious problems can be introduced by hardware, software, and human error; a robust plan will provide for alternate ways around them in order to successfully perform a backup. The backup plan will have a direct impact on the restoration plan (Section 3.4.2) that will itself have to overcome many of the same challenges, thus ensuring the continual availability of data. Finally, as with any plan, it should not be put into action until it has been documented, analysed, reviewed, and tested.

2. Tools

The tools Dump and DD are generally best suited for performing operating system-based backups. However, other tools such as Tar and Cpio are more suitable for user and application- based backups. However, different contexts will require different tools for the specific task. The capabilities and ineffectualness of the various tools are examined in the ensuing sections. Although Dump and DD are preferable for operating system-based backups, Tar and Cpio have their own specific uses and capabilities. It is assumed that the reader is familiar with the aforementioned tools and understands how to implement them. Finally, no commercial backup tool has been examined in this Technical Note in order to maintain tool uniformity with respect to the various Linux distributions currently available on the market.

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