Evaluating the Current System Setup

Zones can be used on any machine that runs the Oracle Solaris 10 or later release. The following primary machine considerations are associated with the use of zones.

• The performance requirements of the applications running within each zone.

• The availability of disk space to hold the files that are unique within each zone.

Disk Space Requirements

There are no limits on how much disk space can be consumed by a zone. The global administrator or a user with appropriate authorizations is responsible for space restriction. The global administrator must ensure that local storage is sufficient to hold a non-global zone's root file system. Even a small uniprocessor system can support a number of zones running simultaneously.

The nature of the packages installed in the non-global zone affects the space requirements of the zones. The number of packages is also a factor.

The disk requirements are determined by the disk space used by the packages currently installed in the global zone and the installed software.

A zone requires a minimum of 150 megabytes of free disk space per zone. However, the free disk space needed is generally from 500 megabytes to 1 gigabyte when the global zone has been installed with all of the standard Oracle Solaris packages. That figure can increase if more software is added.

An additional 40 megabytes of RAM per zone are suggested, but not required on a machine with sufficient swap space.

Restricting Zone Size

You can use ZFS dataset quotas with zones that have zonepaths backed by ZFS datasets to restrict zone size. Administrators that can access zonepath datasets can modify the datasets' quota, userquota, groupquota, and refquota properties to control the maximum amount of disk space that each zone can consume. These properties are described in the zfs(1M) man page.

Administrators can also create ZFS volumes with fixed sizes and install zones in the volume's datasets. The volumes will limit the sizes of the zones installed within them.