If IPv6 is bound to the server, is Hestia protected by the fail2ban and iptables services? Do they work correctly with such IPv6?
There is currently by default no service listed if you have modified your system to listen you have to config it self. Ipv6 support is planned for the next “major” release. Depending on the time we have it will take a while… As we have to rewrite a lot of code.
Is it not safe to have IPv6 for the server?
Ipv6 is only unsafe if not properly deployed. Because people don’t understand it fully yet, it’s often suggested to disable it for security. Is not because it by itself is dangerous and insecure but handling it wrong is what is insecure. The same can go for IP4
If the server has been set up with the default setup nothing should listen to ipv6 ip so it should not matter.