[syslog-ng] Check connection to server

Hello again. I had my syslog server configured and running. All servers has public IP but they are on the same LAN. Now I want to get all logs from a remote server. I configured the remote server same as LAN servers but there is no logs from WAN. How could I check if it is sending data to my syslog server? Maybe I must configure filters to do that? Thanks and best regards.