What are the ports required for synchronization?

If you're trying to synchronize two or more R3000s, make sure that the servers are permitted to communicate with each other using the following TCP ports:

26262

26268

Please note: In a synchronized environment, each R3000 is allowing synchronization requests from the actual IP address of the other R3000 (as determined in the synchronization setup page on each server). If you have a proxy server or firewall that changes the IP address, synchronization will fail.