We are upgrading from 10.2 to 10.4 environment.
Is it possible to share the same mxd to both a test arcgisserver and a production arcgisserver simultaneously?
No, you have to publish to each individually.
Robert is correct. Esri recommends looking at a Python script to publish a service definition file from the mxd, and then copy/upload to both servers. It's not too complicated once you get used to arcpy.
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