I have four sites around Costa Rica in Central America. Is it possible merge the information that i upload to Flightaware servers in only one map?
VRS will do it.
virtualradarserver.co.uk/
You can also use beast_splitter to send the data to a consolidated device.
The consolidated device should not connect to FA. It should just be used to display the combined results.
The four device are in different place (several miles away), and all are RPi, then in this condition is it possible?
As long as you can conect to them using an IP address, then VRS will connect to the Beast binary format of each receiver. Then you can use the merge config to put all the data together on one screen.
When you go to the VRS web radar screen there is a menu option to select the merged receiver, or each individual receiver.
I am using an old raspi 1 without ADS-B receiver where I installed dump1090-fa with the option --net-only and no piaware client. From my three other raspis data is collected by modesmixer2 and fed to this dump1090-fa instance on port 30104 where ADS-B data as well as all MLAT data is displayed. For this setup, you need either a VPN connecting the sites as I do or a known public IP address of either the site where the data should be combined or the sites where data is received. You may need to setup some port forwardings on your internet routers.