Add failed attempt at static IPv6 address.

I feel like I'm close, but this doesn't work.
The problem is when I add this no IPv6 requests can route, in or out.

quinn/etc/nixos/configuration.nix

@@ -181,6 +181,16 @@
   # Enable the OpenSSH daemon.
   services.openssh.enable = true;
 
+  # Enable radvd for advertising IPv6 local addresses
+  #services.radvd.config = ''
+    #interface enp2s0 {
+      #AdvDefaultLifetime 0;
+      #AdvSendAdvert on;
+      #prefix fc00::5/48 { };
+    #};
+  #'';
+  #services.radvd.enable = true;
+
   # Set up a samba share for the scanner
   services.samba = {
     enable = true;
@@ -222,6 +232,12 @@
     ];
   };
 
+  #networking.interfaces = {
+    #enp2s0.ipv6.addresses = [{
+      #address = "fc00:0000:000::5";
+      #prefixLength = 48;
+    #}];
+  #};
   # Copy the NixOS configuration file and link it from the resulting system
   # (/run/current-system/configuration.nix). This is useful in case you
   # accidentally delete configuration.nix.