moved common out of systems

common/global/fail2ban.nix

@@ -0,0 +1,14 @@
+{ config, lib, ... }:
+{
+  services.fail2ban = {
+    enable = lib.mkIf config.networking.firewall.enable (lib.mkDefault true);
+    maxretry = 5;
+    bantime = "24h";
+    bantime-increment = {
+      enable = true;
+      formula = "ban.Time * math.exp(float(ban.Count+1)*banFactor)/math.exp(1*banFactor)";
+      maxtime = "168h";
+      overalljails = true;
+    };
+  };
+}