Incoming connection from unknown ip adress

[MartenW]

My Domoticz installation was, until now not secured with a user/password. Resulting in a hack and switching on lights in the middle of the night. The used ip numbers are from users in China.
A learning experience.
I have now secured my Domoticz / RaspberryPi installation but in the log I still see entry's from Chinese ip numbers with the notation incoming connection. My questions are:
are the Chinese still capable of fooling around with my devices.
And so yes, what to do to prevent this

[emme]

did you forward your Domoticz IP to the utside world?

to protect yourself you can install fail2ban on your rbpi (http://www.fail2ban.org/wiki/index.php/Main_Page)

if you have a programmable firewall and you are familiar with iptables, you can reject incoming connection from those IP you are quite sure are useless

I have a DD-WRT router and I have dropped an entire subnet from UCLA, Shangai, Taipei and Mumbay

[MartenW]

Thanks for the reply's.
Unfortunately no programmable firewall. However to drop networks, there are a lot, more than 20 different ip adresses (111/5/120/189/103 etc.etc.).
The only thing that worries me is of those vandals have put a backdoor in the os of the rpi. I don't know of that is possible with the active Domoticz application.
So, now busy with the creation of a vpn, to combine the rpi remote with a remote ftp server.

[MartenW]

I was looking at the firewall of my internet provider, but never thougt about the firewall in the pi/raspbian. Thanks for the tip.

[ayasystems]

I'm using nignix to open my domoticz to Internet. Nginx only ask password from Internet. I have no problems with this setup

Regards