Zones Overview

The Oracle Solaris Zones partitioning technology is used to virtualize operating system services and provide an isolated and secure environment for running applications. A non-global zone, referred to as a zone, is a virtualized operating system environment created within a single instance of the Oracle Solaris operating system. The instance of the operating system is called the global zone.

The goal of virtualization is to move from managing individual datacenter components to managing pools of resources. Successful server virtualization can lead to improved server utilization and more efficient use of server assets. Server virtualization is also important for successful server consolidation projects that maintain the isolation of separate systems.

Virtualization is driven by the need to consolidate multiple hosts and services on a single machine. Virtualization reduces costs through the sharing of hardware, infrastructure, and administration. Benefits include the following:

• Increased hardware utilization

• Greater flexibility in resource allocation

• Reduced power requirements

• Fewer management costs

• Lower cost of ownership

• Administrative and resource boundaries between applications on a system

When you create a zone, you produce an application execution environment in which processes are isolated from the rest of the system. This isolation prevents processes that are running in one zone from monitoring or affecting processes that are running in other zones. Even a process running with root credentials cannot view or affect activity in other zones. With Oracle Solaris Zones, you can maintain the one-application-per-server deployment model while simultaneously sharing hardware resources.

A zone also provides an abstract layer that separates applications from the physical attributes of the machine on which they are deployed. Examples of these attributes include physical device paths.

Zones can be used on any machine that is running the Oracle Solaris 10 or later Oracle Solaris release. The upper limit for the number of zones on a system is 8192. The number of zones that can be effectively hosted on a single system is determined by the total resource requirements of the application software running in all of the zones, and the size of the system.

These concepts are discussed in Chapter 17, Planning and Configuring Non-Global Zones (Tasks).