Running Global Projects
Updates and Synchronisation
: Manual Updates
Manual Updates
Manual updates can also be carried out at both Hub and Satellite locations. This is a two-way process that can take place between neighbouring Locations. Data will be both sent and received from the location initiating the update, according to which Location has the most up-to-date version of the database.
If update is used between two locations which are not neighbours, then Global will attempt to synchronise the database at the two locations as follows:
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If the sending location is the primary location, it will update the database at each location along the network path to the destination;
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If the receiving location is the primary location, it will execute a SYNCHRONISE command to request an update from the primary location
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If the primary location lies between the two locations, then it will synchronise the database at the sending location with the primary location and update the database from the primary location to the destination location.
It is also possible to do a direct update between two non-neighbour locations using the UPDATE DIRECT command. However this is not recommended, since it can result in ‘Reverse propagation’ errors from scheduled updates. This happens because UPDATE DIRECT results in the database being more recent at the secondary destination of the update than at the intermediate satellite through which scheduled updates are routed.
To learn more about Reverse Propagation errors, see
Recovery from Reverse Propagation Errors
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