Governance Engine Hosting Servers¶
An engine host is an OMAG Server that hosts one or more governance engines. Governance engines define collections of governance services used to automate governance activity in the digital landscape. The governance services within the governance engines may access third party technology to perform their responsibilities or implement their behavior directly.
The engine host uses a metadata access server to retrieve the definitions of the governance engines and the governance services within them. These definitions are retrieved through the Governance Engine OMAS. The Governance Engine OMAS also manages the definition of governance action processes that choreograph calls to the services in a governance engine in order to implement technical controls in the governance program.
Typically, an engine host is deployed close to where the artifacts/resources/data are stored because it can generate a lot of network traffic when its services are running. Multiple engine hosts may run the same governance engine to provide horizontal scalability.
The metadata interfaces needed by the governance engines are provided by the Open Metadata Engine Services (OMES) (or engine services for short). The engine services also run in the engine host.
There are seven types of governance services. Related governance services are packaged together in a specific type of governance engine and enabled in one or more Engine Host OMAG Servers. They run in the appropriate Open Metadata Engine Service (OMES) as shown in the table below.
|Governance Service||Description||Governance Engine type||Engine Service|
|Open Discovery Service||Analyses the content of an Asset's real-world counterpart (resource) in the digital landscape. (For example, if the asset describes a file, the open discovery service analyses the data stored in the file).||Open Discovery Engine||Asset Analysis OMES|
|Watchdog Governance Service||Monitors changes to open metadata elements and when certain changes occur (such as the creation of a new Asset) the watchdog service requests action from other governance services by creating either a Governance Action, a Governance Action Process or an Incident Report.||Governance Action Engine||Governance Action OMES|
|Verification Governance Service||Tests the properties of specific open metadata elements to ensure they are set up correctly or do not indicate a situation where governance activity is required. The results returned from the verification service can be used to trigger other governance services as part of a Governance Action Process.||Governance Action Engine||Governance Action OMES|
|Triage Governance Service||Makes decisions on how to handle a specific situation or incident. Often this involves a human decision maker.||Governance Action Engine||Governance Action OMES|
|Remediation Governance Service||Corrects errors in open metadata or the digital landscape it represents.||Governance Action Engine||Governance Action OMES|
|Provisioning Governance Service||Configuring, enabling, provisioning resources in the digital landscape. Often these provisioning services manage the cataloguing of new assets and the lineage between them.||Governance Action Engine||Governance Action OMES|
|Repository Governance Service||Performs governance for open metadata repositories such as dynamically maintaining open metadata archives.||Repository Governance Engine||Repository Governance OMES|
The name and URL root of the server where the partner metadata service is running is needed to configure an engine service. This is the metadata service used to access open metadata when a governance service runs. The open metadata server configured for the engine host is used to retrieve the governance engine definitions for the governance engines configured for each engine service. The metadata access servers used by the engine services does not need to be the same metadata server as the one used by the engine host server. This enables the management of metadata about the assets to be maintained close to the assets, and the definitions of the governance engines, services and processes to be maintained close to the governance team:
The engine host services have a REST API to query the status of the governance engines running in the engine services. The engine services also have a REST API to query specific details of their governance engines. All these REST APIs may be called by a view server as part of the support for a user interface.