I was half way updating my ISPConfig to 3.1.11 when I enter after saying yes to SSL. I immediately cancelled and then re-update again. This time round nginx could be restarted and I realized the created SSL files has overwritten my LetsEncrypt causing error as follows: I restored the LE backup and it all when smooth again. However, when I am trying to access my Control Panel, I got the following warning: Luckily I can access my Control Panel via other domain / IP but I still need to know what should I do to overcome / remove the above "possible attack" warning?
Try to set the ids anon score to a higher value in /usr/local/ispconfig/security/security_settings.ini
Thank you for the tip @till. I noted that the warning has gone this very next day without changing anything. So, I'll keep default setting as it is for now.
As always, @till , thank you so much for your answers — I was stumped with the same error and all I thought was that somehow fail2ban was acting in the background with some configuration I couldn't find. I hadn't realised that the latest versions of ISPConfig have their own, independent security 'module' (or how you wish to call it) — now I've read the article explaining why and how this was added, and the explanations on /usr/local/ispconfig/security/README.txt are also very clear and easy to follow. I feel a lot better now that I know that ISPConfig has an extra layer of protection, independent of all the rest, even if took getting blocked to learn about it first