Implementing Backup and Recovery: The Readiness Guide for the Enterprise

Many commercial backup products are available on the market today. The leader amongst them on UNIX platforms is VERITAS Software's NetBackup DataCenter. We will use this product, which we refer to as just NetBackup, in our explanations and examples of setting up a backup domain. We start with an introduction to NetBackup, including an explanation of the unique architecture of the product, and then we define the terms that it uses. Most of the examples use the latest release, 4.5, but we will mention when there is a significant difference with older releases.

NetBackup Tiered Architecture

NetBackup uses a four-tiered architecture for backup domains, as shown in Figure 3.1.

The tiers are as follows:

• Client. Any system that contains data that needs to be backed up.

• Media server. Any system that has physically connected storage devices to be used for backups. These can be robotic devices, standalone tape drives, or optical storage devices.

• Master. The NetBackup server that provides administration and control for backups and restores for all clients and servers. It is also the system that contains all the catalog information for the backup domain.

• Global Data Manager. A master of masters that can monitor and facilitate management of multiple master servers and multiple backup domains.

All systems within a NetBackup domain fall within at least one of these tiers and can actually fit into more than one. The first three tiers are always found, even if on the same system. The fourth tier, the Global Data Manager tier, is usually found when there are multiple NetBackup domains that are monitored and administered from a single location. This tiered architecture is one of the things that make NetBackup so scalable and flexible. As you start out, you can have a single master server that gives you a single point of administration, and at the same time, you can have as many media servers as are needed to support your configuration. As you grow, you can add more tape devices and just add more media servers without having a great impact on your overall configuration. If your enterprise continues to grow, you can simply add another master server with media servers as needed. At this point, you might add the fourth tier. The first tier, clients, can be added or deleted easily, since the configuration is kept on the master server.

Figure 3.1: NetBackup tiered architecture.