Do I need to open port 23560 to use remote probe? Which direction?

By default, the port used on remote probe is 23560. I would like to know if, when the remote probe is behind a firewall, I need to open port 23560 on my firewall´s rules, and which direction. Both directions?

Yes, you need to open port 23560 for remote probes. The traffic is initiated from the remote probe to the PRTG core server, so you should open port 23560 outbound from the remote probe to the core server. This ensures proper communication between the remote probe and the PRTG core server. 

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