Add new configuration for apex

Reviewed-by: Aleix Boné <abonerib@bsc.es>

m/apex/configuration.nix

@@ -0,0 +1,58 @@
+{ lib, config, pkgs, ... }:
+
+{
+  imports = [
+    ../common/xeon.nix
+    ../common/ssf/hosts.nix
+    ../module/ceph.nix
+    ./nfs.nix
+  ];
+
+  # Don't install grub MBR for now
+  boot.loader.grub.device = "nodev";
+
+  boot.initrd.kernelModules = [
+    "megaraid_sas" # For HW RAID
+  ];
+
+  fileSystems."/home" = {
+    device = "/dev/disk/by-label/home";
+    fsType = "ext4";
+  };
+
+  # No swap, there is plenty of RAM
+  swapDevices = lib.mkForce [];
+
+  networking = {
+    hostName = "apex";
+    defaultGateway = "84.88.53.233";
+    nameservers = [ "8.8.8.8" ];
+
+    # Public facing interface
+    interfaces.eno1.ipv4.addresses = [ {
+      address = "84.88.53.236";
+      prefixLength = 29;
+    } ];
+
+    # Internal LAN to our Ethernet switch
+    interfaces.eno2.ipv4.addresses = [ {
+      address = "10.0.40.30";
+      prefixLength = 24;
+    } ];
+
+    # Infiniband over Omnipath switch (disconnected for now)
+    # interfaces.ibp5s0 = {};
+
+    nat = {
+      enable = true;
+      internalInterfaces = [ "eno2" ];
+      externalInterface = "eno1";
+    };
+  };
+
+  # Use tent for cache
+  nix.settings = {
+    extra-substituters = [ "https://jungle.bsc.es/cache" ];
+    extra-trusted-public-keys = [ "jungle.bsc.es:pEc7MlAT0HEwLQYPtpkPLwRsGf80ZI26aj29zMw/HH0=" ];
+  };
+}