As the title says, I want to know the most paranoid security measures you’ve implemented in your homelab. I can think of SDN solutions with firewalls covering every interface, ACLs, locked-down/hardened OSes etc but not much beyond that. I’m wondering how deep this paranoia can go (and maybe even go down my own route too!).
Thanks!
Fail2ban yes; one year, however, is IMO a bit excessive.
Most ISP IP assignments do tend to linger - even with DHCP the same IP will be re-assigned to the same gateway router for quite a number of sequential times - but most IPs do eventually change within a few months. I personally use 3 months as a happy medium for any blacklist I run. Most dynamic IPs don’t last this long, almost all attackers will rotate through IPs pretty quickly anyhow, and if you run a public service (website, etc.), blocking for an entire year may inadvertently catch legitimate visitors.
Plus, you also have to consider the load such a large blocklist will have on your system, if most entries no longer represent legitimate threat actors, you’ll only bog down your system by keeping them in there.
Fail2ban can be configured to allow initial issues to cycle back out quicker, while blocking known repeat offenders for a much longer time period. This is useful in keeping block lists shorter and less resource-intensive to parse.
My block list is very small actually due to the non standard ssh port. Everything else goes through wireguard.
If it was open to the public then yes I’d have to reconsider the ban length.
That makes a lot more sense for your setup, then.