Autonomous Site Operation
Large scale installations of system:inmation can face challenges when relying on a single Core component to direct all the data flow for a global network of sites. Continuous connection between all global sites is not always guaranteed and if there is an outage or break in communication between a single central Core and for example, a remote Connector, the site could feasibly be offline for an extended period of time. This would mean on-site history queries would be unavailable, data archiving would cease and system updates would be unavailable. By creating local Core components for global sites that sit beneath an overall Master Core component, the site can operate with autonomy, whilst continuing to maintain the benefits of a centralized system.
The installation of Local Core components, enables separate sites to operate autonomously during disconnection from the central Master Core installation at headquarters. Local Cores operate with their own MongoDB Data Stores that are accessible site-wide, during offline events. The gathered data is kept in the Store and Forward buffers of the Local Core and Connectors until the targeted System and Local Data Stores have archived the data.
The Local Core components can be accessed as separate entities using DataStudio and the Web API. This allows for on-site access to the Core and locally stored historical data, even during global outages. The Local Cores make use of the Custom Time Series Data Store feature to archive data locally as well as in the central System Data Stores. This enables data to be persisted locally and avoids potential data loss if the System Data Store is offline for long time periods.
Local Cores running below a Master Core are the children of the Master Core object in the hierarchy. A user connected to the Master Core can create/update/delete objects beneath the Local Core. However, in the opposite scenario (user connected to a Local Core), the user would not be able to perform the same actions below the Master Core object.
If connected to a Local Core (for example with a client application like DataStudio), the user is able to view the Master Core and System objects in the I/O Model but cannot view any other children below the Master Core unless they connect directly to the Master Core.
With this configuration, the Local Core can autonomously exist without a Master Core connection and still be able to archive and retrieve historical data.