If only the config of an instance is updated the dirty flag of the
instance is not set, which results in changes being discarded when the
controller shuts down afterwards.
Fix by always triggering the update logic when an instance field is
changed.
If the controller is behind a proxy then the socket.remoteAddress will
be that of the proxy instead of the end client that connected. In this
case the X-Forwarded-For header will contain the address of the end
client, but this should only be relied upon if the party connecting is a
trusted proxy, otherwise a malicious user could spoof the IP address
that is logged by providing a forged X-Forwarded-For header.
Implement a trusted proxy list consisting of a configured list of IP
addresses and/or CIDR blocks and use the last address[1] in the
X-Forwarded-For header if the remoteAddress address of the connecting
party is in the trusted proxy list.
[1]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Forwarded-For