Server Administration Guide - Define the Writeable Period for Modified and Annotation Data (Historic Data Storage Settings)

Define the Writable Period for Modified and Annotation Data

It is assumed that the amount of modified historic data and annotation records for historic data, created over the lifetime of a system, will be relatively small and does not need to be archived to disk. Due to the small size of modified historic data and annotation records for historic data, they are stored permanently online.

Although the modified historic data and annotation records for historic data are store indefinitely, the system defines the maximum period that this data is writable.

For multi-server systems, this period also corresponds to the maximum period that the data is synced between servers.

By default, each server is set to allow modified historic data and annotations to be writable and synced for 520 weeks (10 years). For many systems, this setting is appropriate. However, you may choose to extend the number of weeks if your system is expected to continue running for over 10 years. Extending the number of weeks will mean that the modified historic data and annotations can be modified and synced for a longer time. Increasing the syncable period affects the initial synchronization time of standby servers, and although the few data changes made need to be synchronized, the data for the whole period is checked during the initial synchronization. The extra demand, resulting from a longer period, on the resources of the server is negligible and is unlikely to affect the overall system performance.

Defining the Writable and Syncable period

To specify the period for modified historic data and annotations:

Expand the Historic Configuration branch.Access the Geo SCADA Expert Server Configuration Tool.
Select the Historic Data type.
Define the following fields:

Modified data writable for

Define the amount of period for which the server allows modified historic data to be writable and synced. The default setting is 520 weeks (10 years).

Annotation data

Define the amount of time for which the server allows annotation records to be writable and synced. The default setting is 520 weeks (10 years).
Apply the changes to the server.

If the system contains more data than the syncable period defined and you are transferring Geo SCADA Expert to a new server, you will need to copy the modified historic data and annotation record files manually.