linux4u.nz

Fail2ban is my choice for preventing breaches, it's highly configurable and blocks attacks or persistent users instantly, keeping the system safe and running smoothly.

I've used almost every flavour of linux and I always end up back with an RHEL OS for ease of use and stability.

Kali is great for penetration testing but the updates come so hard and fast you have to be careful things don't break.

https://zonemaster.nz

Zonemaster performs many tests, such as checking DNSSEC signatures, or that different hosts can be accessed and that IP addresses are valid. This is all to make sure that your domain name runs as smoothly as possible.