Are the sync services "required" to set a remote tag provider between edge and full ignition server?
I'm not getting a connection, and it seems like it should be simple since the main server can see the edge server.
Edge is setup a bit different in terms of the GAN. In order to do remote history you have to you use the data sync
but for the remote tag provider if you mean seeing the edge provider in another gateway then you should just be able to use the GAN.
You will not be able to see other providers inside of the edge gateway however.