Solaris Containers: Resource Management and Solaris Zones Developer's Guide

Zones Overview

A zone is a virtualized operating system environment that is created within a single instance of the Solaris Operating System. Zones are a partitioning technology that provides an isolated, secure environment for applications. 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 a process that is running in one zone from monitoring or affecting processes that are running in other zones. Even a process running with superuser credentials cannot view or affect activity in other zones. A zone also provides an abstract layer that separates applications from the physical attributes of the machine on which the zone is deployed. Examples of these attributes include physical device paths and network interface names.

By default, all systems have a global zone. The global zone has a global view of the Solaris environment in similar fashion to the superuser model. All other zones are referred to as non-global zones. A non-global zone is analogous to an unprivileged user in the superuser model. Processes in non-global zones can control only the processes and files within that zone. Typically, system administration work is mainly performed in the global zone. In rare cases where a system administrator needs to be isolated, privileged applications can be used in a non-global zone. In general, though, resource management activities take place in the global zone.