Enable alternative IP Detection for logging and ipblock checking,

[pulponair]

Scenario:
If there is any sort of proxy or caching server in front of your actuall application server (e.g. varnish or nginx proxy/lb) $_SERVER['REMOTE_ADDRESS'] may alway contain 127.0.0.1

That issue is related to logging and the ipblocking Interceptor. And may result in your forms getting blocked.

Solution 1:
Introduce some sort of automatic detection e.g.:
check if REMOTE_ADDRESS points to 127.0.0.1 and check for the existens of e.g. $_SERVER['HTTP_X_REAL_IP'] (Might varydepending on the actuall infrastructure).

Solution 2:
Introduce some sort of configuration for that.

Note:
Keep in mind that \TYPO3\CMS\Core\Utility\GeneralUtility::getIndpEnv is not aware of any key in e.g. $_SERVER.