How to whitelist another server's IP and keep this server secure

[appbook]

Hello,

I need to sync files from the main server to a remote server with the "rsync" command in a scheduled job which runs frequently, however I can't sync files successfully without whitelisting another server's IP with csf on both side. I'm concerned that adding the remote server's IP address to the whitelist of the main server, will cause the security issue, if the remote server is hacked, is my main server in dangerous? How can I do it in a secure way?

Thanks in advance.

Regards.

[postcd]

Im noob, this is what i think:

Try to allow that IP in Firewall, example add to: /etc/csf/csf.allow
You should not have an issue connecting. or add to /etc/csf/csf.ignore and that IP should not be banned if any firewall rule is triggered.
Still it should not be much insecure to allow IP this way. if that server got hacked, you are still password protected right? I would not be worried.