diff --git a/config/cluster.nix b/config/cluster.nix
index 0c73114..c8bc5cd 100644
--- a/config/cluster.nix
+++ b/config/cluster.nix
@@ -118,8 +118,6 @@
       };
     };
     subnet4 = "172.20.77.0/27";
-    subnet4Len = 27;
-    subnet4Net = "172.20.77.0";
     subnets6 = {
       dn42 = "fd23:42:c3d2:586::/64";
       up4 = "2a00:8180:2c00:284::/64";
diff --git a/config/core.nix b/config/core.nix
index 5969f76..86db288 100644
--- a/config/core.nix
+++ b/config/core.nix
@@ -190,8 +190,6 @@
       };
     };
     subnet4 = "172.20.72.0/25";
-    subnet4Len = 25;
-    subnet4Net = "172.20.72.0";
     subnets6 = {
       dn42 = "fd23:42:c3d2:581::/64";
       up4 = "2a00:8180:2c00:281::/64";
diff --git a/config/mgmt.nix b/config/mgmt.nix
index 96b816b..cbae65b 100644
--- a/config/mgmt.nix
+++ b/config/mgmt.nix
@@ -174,8 +174,6 @@
       };
     };
     subnet4 = "10.0.0.0/24";
-    subnet4Len = 24;
-    subnet4Net = "10.0.0.0";
     subnets6 = { dn42 = "fd23:42:c3d2:580::/64"; };
   };
 
diff --git a/config/priv.nix b/config/priv.nix
index 614df8a..3557748 100644
--- a/config/priv.nix
+++ b/config/priv.nix
@@ -17,8 +17,6 @@
         up4 = { priv1-gw = "2a00:8180:2c00:2c0::1"; };
       };
       subnet4 = "172.20.74.0/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.0";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5c0::/64";
         up4 = "2a00:8180:2c00:2c0::/64";
@@ -41,8 +39,6 @@
         up4 = { priv10-gw = "2a00:8180:2c00:2c9::1"; };
       };
       subnet4 = "172.20.74.96/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.96";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5c9::/64";
         up4 = "2a00:8180:2c00:2c9::/64";
@@ -65,8 +61,6 @@
         up4 = { priv11-gw = "2a00:8180:2c00:2ca::1"; };
       };
       subnet4 = "172.20.74.160/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.160";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5ca::/64";
         up4 = "2a00:8180:2c00:2ca::/64";
@@ -89,8 +83,6 @@
         up4 = { priv12-gw = "2a00:8180:2c00:2cb::1"; };
       };
       subnet4 = "172.20.74.224/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.224";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5cb::/64";
         up4 = "2a00:8180:2c00:2cb::/64";
@@ -113,8 +105,6 @@
         up4 = { priv13-gw = "2a00:8180:2c00:2cc::1"; };
       };
       subnet4 = "172.20.75.32/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.32";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5cc::/64";
         up4 = "2a00:8180:2c00:2cc::/64";
@@ -137,8 +127,6 @@
         up4 = { priv14-gw = "2a00:8180:2c00:2cd::1"; };
       };
       subnet4 = "172.20.75.96/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.96";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5cd::/64";
         up4 = "2a00:8180:2c00:2cd::/64";
@@ -161,8 +149,6 @@
         up4 = { priv15-gw = "2a00:8180:2c00:2ce::1"; };
       };
       subnet4 = "172.20.75.160/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.160";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5ce::/64";
         up4 = "2a00:8180:2c00:2ce::/64";
@@ -185,8 +171,6 @@
         up4 = { priv16-gw = "2a00:8180:2c00:2cf::1"; };
       };
       subnet4 = "172.20.75.224/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.224";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5cf::/64";
         up4 = "2a00:8180:2c00:2cf::/64";
@@ -212,8 +196,6 @@
         up4 = { priv17-gw = "2a00:8180:2c00:2d0::1"; };
       };
       subnet4 = "172.20.73.128/27";
-      subnet4Len = 27;
-      subnet4Net = "172.20.73.128";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5d0::/64";
         up4 = "2a00:8180:2c00:2d0::/64";
@@ -236,8 +218,6 @@
         up4 = { priv18-gw = "2a00:8180:2c00:2d1::1"; };
       };
       subnet4 = "172.20.74.48/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.48";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5d1::/64";
         up4 = "2a00:8180:2c00:2d1::/64";
@@ -260,8 +240,6 @@
         up4 = { priv19-gw = "2a00:8180:2c00:2d2::1"; };
       };
       subnet4 = "172.20.73.192/26";
-      subnet4Len = 26;
-      subnet4Net = "172.20.73.192";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5d2::/64";
         up4 = "2a00:8180:2c00:2d2::/64";
@@ -288,8 +266,6 @@
         up4 = { priv2-gw = "2a00:8180:2c00:2c1::1"; };
       };
       subnet4 = "172.20.75.0/27";
-      subnet4Len = 27;
-      subnet4Net = "172.20.75.0";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5c1::/64";
         up4 = "2a00:8180:2c00:2c1::/64";
@@ -312,8 +288,6 @@
         up4 = { priv20-gw = "2a00:8180:2c00:2d3::1"; };
       };
       subnet4 = "172.20.74.112/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.112";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5d3::/64";
         up4 = "2a00:8180:2c00:2d3::/64";
@@ -336,8 +310,6 @@
         up4 = { priv21-gw = "2a00:8180:2c00:2d4::1"; };
       };
       subnet4 = "172.20.74.144/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.144";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5d4::/64";
         up4 = "2a00:8180:2c00:2d4::/64";
@@ -360,8 +332,6 @@
         up4 = { priv22-gw = "2a00:8180:2c00:2d5::1"; };
       };
       subnet4 = "172.20.74.176/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.176";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5d5::/64";
         up4 = "2a00:8180:2c00:2d5::/64";
@@ -389,8 +359,6 @@
         up4 = { priv23-gw = "2a00:8180:2c00:2d6::1"; };
       };
       subnet4 = "172.20.73.160/27";
-      subnet4Len = 27;
-      subnet4Net = "172.20.73.160";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5d6::/64";
         up4 = "2a00:8180:2c00:2d6::/64";
@@ -413,8 +381,6 @@
         up4 = { priv24-gw = "2a00:8180:2c00:2d7::1"; };
       };
       subnet4 = "172.20.74.240/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.240";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5d7::/64";
         up4 = "2a00:8180:2c00:2d7::/64";
@@ -437,8 +403,6 @@
         up4 = { priv25-gw = "2a00:8180:2c00:2d8::1"; };
       };
       subnet4 = "172.20.74.80/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.80";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5d8::/64";
         up4 = "2a00:8180:2c00:2d8::/64";
@@ -461,8 +425,6 @@
         up4 = { priv26-gw = "2a00:8180:2c00:2d9::1"; };
       };
       subnet4 = "172.20.75.48/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.48";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5d9::/64";
         up4 = "2a00:8180:2c00:2d9::/64";
@@ -485,8 +447,6 @@
         up4 = { priv27-gw = "2a00:8180:2c00:2da::1"; };
       };
       subnet4 = "172.20.75.80/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.80";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5da::/64";
         up4 = "2a00:8180:2c00:2da::/64";
@@ -509,8 +469,6 @@
         up4 = { priv28-gw = "2a00:8180:2c00:2db::1"; };
       };
       subnet4 = "172.20.75.112/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.112";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5db::/64";
         up4 = "2a00:8180:2c00:2db::/64";
@@ -533,8 +491,6 @@
         up4 = { priv29-gw = "2a00:8180:2c00:2dc::1"; };
       };
       subnet4 = "172.20.75.144/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.144";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5dc::/64";
         up4 = "2a00:8180:2c00:2dc::/64";
@@ -557,8 +513,6 @@
         up4 = { priv3-gw = "2a00:8180:2c00:2c2::1"; };
       };
       subnet4 = "172.20.74.128/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.128";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5c2::/64";
         up4 = "2a00:8180:2c00:2c2::/64";
@@ -581,8 +535,6 @@
         up4 = { priv30-gw = "2a00:8180:2c00:2dd::1"; };
       };
       subnet4 = "172.20.75.176/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.176";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5dd::/64";
         up4 = "2a00:8180:2c00:2dd::/64";
@@ -605,8 +557,6 @@
         up4 = { priv31-gw = "2a00:8180:2c00:2de::1"; };
       };
       subnet4 = "172.20.75.208/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.208";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5de::/64";
         up4 = "2a00:8180:2c00:2de::/64";
@@ -629,8 +579,6 @@
         up4 = { priv32-gw = "2a00:8180:2c00:2df::1"; };
       };
       subnet4 = "172.20.75.240/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.240";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5df::/64";
         up4 = "2a00:8180:2c00:2df::/64";
@@ -653,8 +601,6 @@
         up4 = { priv33-gw = "2a00:8180:2c00:2e0::1"; };
       };
       subnet4 = "172.20.74.16/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.16";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5e0::/64";
         up4 = "2a00:8180:2c00:2e0::/64";
@@ -677,8 +623,6 @@
         up4 = { priv34-gw = "2a00:8180:2c00:2e1::1"; };
       };
       subnet4 = "172.20.74.208/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.208";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5e1::/64";
         up4 = "2a00:8180:2c00:2e1::/64";
@@ -701,8 +645,6 @@
         up4 = { priv35-gw = "2a00:8180:2c00:2e2::1"; };
       };
       subnet4 = "172.20.76.0/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.76.0";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5e2::/64";
         up4 = "2a00:8180:2c00:2e2::/64";
@@ -725,8 +667,6 @@
         up4 = { priv36-gw = "2a00:8180:2c00:2e3::1"; };
       };
       subnet4 = "172.20.76.64/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.76.64";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5e3::/64";
         up4 = "2a00:8180:2c00:2e3::/64";
@@ -749,8 +689,6 @@
         up4 = { priv37-gw = "2a00:8180:2c00:2e4::1"; };
       };
       subnet4 = "172.20.76.128/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.76.128";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5e4::/64";
         up4 = "2a00:8180:2c00:2e4::/64";
@@ -773,8 +711,6 @@
         up4 = { priv38-gw = "2a00:8180:2c00:2e5::1"; };
       };
       subnet4 = "172.20.76.192/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.76.192";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5e5::/64";
         up4 = "2a00:8180:2c00:2e5::/64";
@@ -797,8 +733,6 @@
         up4 = { priv39-gw = "2a00:8180:2c00:2e5::1"; };
       };
       subnet4 = "172.20.77.128/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.77.128";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5e6::/64";
         up4 = "2a00:8180:2c00:2e6::/64";
@@ -821,8 +755,6 @@
         up4 = { priv4-gw = "2a00:8180:2c00:2c3::1"; };
       };
       subnet4 = "172.20.75.128/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.128";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5c3::/64";
         up4 = "2a00:8180:2c00:2c3::/64";
@@ -845,8 +777,6 @@
         up4 = { priv40-gw = "2a00:8180:2c00:2e6::1"; };
       };
       subnet4 = "172.20.77.64/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.77.64";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5e7::/64";
         up4 = "2a00:8180:2c00:2e7::/64";
@@ -869,8 +799,6 @@
         up4 = { priv41-gw = "2a00:8180:2c00:2e7::1"; };
       };
       subnet4 = "172.20.77.192/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.77.192";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5e8::/64";
         up4 = "2a00:8180:2c00:2e8::/64";
@@ -893,8 +821,6 @@
         up4 = { priv42-gw = "2a00:8180:2c00:2e8::1"; };
       };
       subnet4 = "172.20.76.32/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.76.32";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5e9::/64";
         up4 = "2a00:8180:2c00:2e9::/64";
@@ -906,8 +832,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv44 = {
@@ -916,8 +840,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv45 = {
@@ -926,8 +848,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv46 = {
@@ -936,8 +856,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv47 = {
@@ -946,8 +864,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv48 = {
@@ -956,8 +872,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv49 = {
@@ -966,8 +880,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv5 = {
@@ -987,8 +899,6 @@
         up4 = { priv5-gw = "2a00:8180:2c00:2c4::1"; };
       };
       subnet4 = "172.20.74.64/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.64";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5c4::/64";
         up4 = "2a00:8180:2c00:2c4::/64";
@@ -1000,8 +910,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv51 = {
@@ -1010,8 +918,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv52 = {
@@ -1020,8 +926,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv53 = {
@@ -1030,8 +934,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv54 = {
@@ -1040,8 +942,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv55 = {
@@ -1050,8 +950,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv56 = {
@@ -1060,8 +958,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv57 = {
@@ -1070,8 +966,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv58 = {
@@ -1080,8 +974,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv59 = {
@@ -1090,8 +982,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv6 = {
@@ -1111,8 +1001,6 @@
         up4 = { priv6-gw = "2a00:8180:2c00:2c5::1"; };
       };
       subnet4 = "172.20.74.192/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.192";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5c5::/64";
         up4 = "2a00:8180:2c00:2c5::/64";
@@ -1124,8 +1012,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv61 = {
@@ -1134,8 +1020,6 @@
       hosts4 = { };
       hosts6 = { };
       subnet4 = null;
-      subnet4Len = null;
-      subnet4Net = null;
       subnets6 = { };
     };
     priv7 = {
@@ -1155,8 +1039,6 @@
         up4 = { priv7-gw = "2a00:8180:2c00:2c6::1"; };
       };
       subnet4 = "172.20.75.64/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.64";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5c6::/64";
         up4 = "2a00:8180:2c00:2c6::/64";
@@ -1179,8 +1061,6 @@
         up4 = { priv8-gw = "2a00:8180:2c00:2c7::1"; };
       };
       subnet4 = "172.20.75.192/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.75.192";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5c7::/64";
         up4 = "2a00:8180:2c00:2c7::/64";
@@ -1203,8 +1083,6 @@
         up4 = { priv9-gw = "2a00:8180:2c00:2c8::1"; };
       };
       subnet4 = "172.20.74.32/28";
-      subnet4Len = 28;
-      subnet4Net = "172.20.74.32";
       subnets6 = {
         dn42 = "fd23:42:c3d2:5c8::/64";
         up4 = "2a00:8180:2c00:2c8::/64";
diff --git a/config/pub.nix b/config/pub.nix
index 055f6e5..16f8feb 100644
--- a/config/pub.nix
+++ b/config/pub.nix
@@ -13,8 +13,6 @@
     hosts4 = { pub-gw = "172.20.78.1"; };
     hosts6 = { dn42 = { pub-gw = "fd23:42:c3d2:583::1"; }; };
     subnet4 = "172.20.78.0/23";
-    subnet4Len = 23;
-    subnet4Net = "172.20.78.0";
     subnets6 = { dn42 = "fd23:42:c3d2:583::/64"; };
   };
 
diff --git a/config/serv.nix b/config/serv.nix
index 8fd868f..545d276 100644
--- a/config/serv.nix
+++ b/config/serv.nix
@@ -114,8 +114,6 @@
       };
     };
     subnet4 = "172.20.73.0/26";
-    subnet4Len = 26;
-    subnet4Net = "172.20.73.0";
     subnets6 = {
       dn42 = "fd23:42:c3d2:582::/64";
       up4 = "2a00:8180:2c00:282::/64";
diff --git a/nix/lib/config/options.nix b/nix/lib/config/options.nix
index 58b9c63..7503c49 100644
--- a/nix/lib/config/options.nix
+++ b/nix/lib/config/options.nix
@@ -119,6 +119,7 @@ let
             if subnet4 != null && builtins.length s == 2
             then builtins.head s
             else null;
+        description = "Don't set, use subnet4 instead!";
       };
       subnet4Len = mkOption {
         type = with types; nullOr types.int;
@@ -130,6 +131,7 @@ let
             if subnet4 != null && builtins.length s == 2
             then lib.toInt (elemAt s 1)
             else null;
+        description = "Don't set, use subnet4 instead!";
       };
       subnets6 = mkOption {
         description = "IPv6 subnets w/o prefixlen (always 64)";