Host Type Attributes (N1 Service Provisioning System 4.1 User's Guide)

N1 Service Provisioning System 4.1 User's Guide

Host Type Attributes

A host type is distinguished by its name and its attributes. An attribute is a name-value pair. Each attribute may have a default value.

For example, you might define a host type, production_web_hosts, for production servers running a Web application. The table below describes an example of such a host type.

Table 4–3 Host Type Attributes Examples


Attribute Name	Default Value	Comment
name	None.	The name of the host. This attribute is inherited from the `crhost` host type.
description	None.	A description of the host. This attribute is inherited from the `crhost` host type.
location	San Francisco	The name of the data center where the host is located. In this example, an organization has most of its servers in a data center in San Francisco. So, the user has made this the default value.
host_role	web	An identifier for the role this host plays in the Data Center. By default, this variable is assigned the value web, indicating the host acts as a web server.
web_port	80	The number of the port through which users will access this Web application. Because this variable is listed in the host type, it is accessible to plans, command lines, and Web pages and it can be configured dynamically.

Host attributes must begin with a letter and cannot include spaces.

Adding new attributes to the host type results in the attributes and their defaults being added to every host of that type. Removing attributes from a host type permanently deletes those attributes from every host of that type. Attributes cannot be renamed; they can only be deleted and re-added with a new name, which results in the attribute value being reset to the default on all hosts of that type.

When you define a host (an individual target machine), you can selectively override the values of attributes specified by the host's host type. Default values that are not overwritten will be applied to the host.