About Container Definitions

The first step when creating a custom container is to make a container definition. The container definition consists of the following information:

• Name of the container

• Description of the container (optional)

• Project type of the container

• Project name associated with the container

• The UNIX users and groups associated with the container

• The match expression, if there is one

The name you assign to a container definition is permanent and cannot be changed. The project name is likewise permanent. The other identifying information for the container definition can be changed.

The container definition is saved by the software and is available for repeated use until the definition is deleted. The container definition is used when activating a container on a host. A container is active when it has been associated with a host, and its resource reservations have been set.

Because multiple containers, with the same definition and resource reservations, can be active simultaneously on several different hosts, the container definition is a convenience for managing containers across the data center. Once the container definition has been saved, it can be used at any time to activate a container on any suitable host. In this manner the container definition can be used as a template for creating a new container instance.

You can use a container definition to create multiple container instances. For example, if you use a single container definition to create three active containers on three different hosts, you have one container definition and three container instances of that definition. Changing the underlying information in the definition changes all the container instances based on that definition.

The wizard gives you the option to create a container that is activated upon completion of all the steps. A container definition is created at the same time and its name is saved in the GUI. You also have the option to create just the container definition and activate the container at a later time with a wizard that guides you through the process.

For a container definition, you can perform the following tasks using the GUI:

• Create a new container definition

• Create a new group

• Move the container definition into and out of groups

• Modify the properties

• Create a new container instance (active container) on a host

• Delete the container definition

For a container instance, you can perform the following tasks using the GUI:

• Create a new group

• Move the container

• Modify the properties

• Change the resource reservations

• Create a resource change job

• Check the status of the processes running inside

• Request a utilization report and export the data to a file

• Deactivate or activate the container

• Set an alarm

• Delete the container