We added a setting, behind_proxy, in CORE-2349 that sets whether or not Blesta is behind a proxy/load balancer. In such cases, we cannot rely on php's _$SERVER['REMOTE_ADDR'] IP address because it is the IP address of the proxy, not the user. Instead, the proxy should be passing an x-forwarded-for header to identify the user's IP address.
We could update the settings to allow a white-list of IP addresses to be set representing the proxy IP addresses that are trusted, and only interpret x-forwarded-for IPs from those IPs.