Sync Drupal commerce order information Sync Drupal commerce order information between several drupal instances.

Here is my use case.

A business has a Drupal commerce website.
It also has several internal commerce sites.

Each of these has to have the ability to work independently of each other for certain periods of time.
At a later date there will be a mobile app doing the same thing.
So any sales information or orders need to be synced at later points throughout the day.

What is the recommended way to do that securely and also avoid and order related conflicts such as order number customer name changes etc?

I realize this is a fairly broad question but Im not looking for a specific answer,  Any general information or recommendations would be great.
Some general advice: 

I had a similar situation on a project. I first tried various options for importing orders from the separate sites into a central site using modules like:


commerce_order_ftp_export
commerce_export
commerce_export_csv
commerce_feeds with patch for orders


But you will need custom code to resolve order IDs etc. Depending on the number of sites, this may be workable.

However, I eventually opted for a solution as follows:


Using a mobile POS app for sales
Sending sales from each instance of the app into a central drupal installation running maceij’s version of commerce_marketplace
This way,sales can be separated and/or aggregated by location, POS, etc.