All RCP workers have a default firewall configuration that allows only local (same-machine) communication. The firewall configuration file for all repositories is located at:
config/facs/net.config.json
Allow connections from other RPC workers
To allow connections from other RPC workers, add the rpcClientKey (found in the same status file as the rpcPublicKey) to the allow or allowReadOnly(only used for Ork worker) in net.config.json. The allow array can contain multiple client keys.