The BMC Atrium Discovery system is based on a datastore designed to handle very large, complex and interconnected data models. The datastore defines data as a set of objects and the relationships between them.

Objects and Attributes

An object is any data entity of a specific type, or kind, which has characteristics defined by attributes. The types of object permitted and their attributes are defined in the Taxonomy. For example; an object of kind Host has attributes including Processor, Domain, and Operating System. Some attributes have a predefined list of valid values, or are of a specific type, such as a date, a Boolean value, or a list (such as a number of associated IP addresses). However many attributes are defined as strings with no size limit, allowing very flexible data definitions.

Attributes can have one or more of the following flags:

• Required – An attribute that is mandatory when creating data. Required attributes are marked by an asterisk on the user interface.
• Expected or Optional – Defines whether or not an attribute affects the Data Quality of an object. Note that unless the attribute is also marked as Required, an Expected attribute is not mandatory.

Aging

Discovered data is regarded as valid at the time of its last successful scan. The nature of IT infrastructure raises frequent minor changes to configurations, hosts, and software. Consequently, discovered data can be regarded as becoming less relevant with the passing of time, Aging properly reflects this.

The following data items are aged:

• Host
• Software Instance
• Discovery Access

For more information on data aging:

1. Select the Administration tab from the primary navigation bar across the top of the page. The Administration home page is displayed.
2. Click the Model Maintenance icon in the Model section. The Model Maintenance page is displayed.
   
   You can change the BMC Atrium Discovery default settings by selecting the drop-down menus for each setting in the Change To column.

History Data

History information about each object is recorded in the datastore. This audit trail includes details of the changes made, the date and time of the changes and the user who made the changes. Destruction of data is also audited, with destroyed data being marked as virtually destroyed rather than completely removed. You can view the history of each object in the datastore and you can still search for and display details of destroyed objects. For details about how you can view historical comparisons in BMC Atrium Discovery, see Historical Comparison of Nodes.

The history is purged automatically at 22.05 on the first day of each month. For more information on the way in which the history is purged, see Purging the History.

File Attachments

You can associate files of any type with a managed element to provide additional or supporting information.

A managed element is any one of the following:

• Host
• Software Instance
• Business Application Instance
  These files are uploaded to the BMC Atrium Discovery system for easy access in case a Disaster Recovery procedure is needed.

Any number of attachments can be associated with a single object and the same file can be attached to multiple objects. A copy of the attached file is uploaded to the BMC Atrium Discovery appliance for secure storage. You can subsequently view a file or update it at any time. There are no restrictions on the type of file, as BMC Atrium Discovery stores the attachments and does not process them.
Attachments are assigned to a particular category, such as Audit or System Recovery. The BMC Atrium Discovery Administrator can set up additional categories. See Setting Up Standard Data Categories.

Data Quality

Since the data held by the BMC Atrium Discovery system may at times be incomplete, an indication of data quality is maintained and reported for each object. The data quality reporting includes a method for weighting data problems so that an issue defined as serious will have a greater effect on the overall data quality for that object than a minor issue.
To calculate the data quality for an object, each potential data problem, such as a missing attribute value or relationship, is identified and quantified. Each possible problem is assigned a numerical value between 0.1 and 1, where complete and accurate data has a value of 1. The values are used to provide an overall data quality value, which is assigned to one of three categories:

• Good – Data Quality Indicator calculated as over a given high threshold.
• Medium – Data Quality Indicator calculated as between the high and low thresholds.
• Poor – Data Quality Indicator calculated as below the low threshold.
  A background color to an icon indicates its data quality on the View Object and Report pages.

Acquiring Data

The data used by BMC Atrium Discovery can be acquired from the following data sources:

• Discovery – Discovery of your infrastructure is the best way of acquiring information about the hardware in your system and the programs running. For details, see The Discovery Engine.
• The Pattern Language – Data is created using the Pattern Language. The patterns trigger on certain conditions and can create data which models different systems/configurations, for example, Solaris Zones and Virtual Machines. For more information on managing patterns, see Pattern Management.
• Import – Data about your current systems and business can be imported from existing systems such as Asset Management or Inventory systems and from databases. The import process is managed by Tideway Professional Services. For information about importing data, contact Tideway Support.