I am expecting my mail traffic to increase in the future and setting up a local Pyzor server as recommended in the docs. Is there a way to populate this database by syncing with the public Pyzor servers? What is the best way to populate this database?
There's officially no way to do this. Frank Tobin had a plan to start a peering system in 2002, but it never got implemented.
Source: https://sourceforge.net/p/pyzor/mailman/message/1449003/