Sync Setup Notes and Example

There are some known issues, most are listed in this Jira issue

Default example in OFBiz

The example in OFBiz (in specialpurpose/pos/data/PosSyncSettings.xml) is designed for a 3 levels architecture, where Per Store Servers (PSS) are used between POS terminals and the Master Central Server (MCS).
Here is a short explanation on how it works
This setting is intended to synchronise a main database (on the MCS) with the databases of local stores servers (PSS) each of them being synchronised with their local POS terminals. Each of these OFBiz instances use a database. Store here means a physical store where POS terminals are.

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