add server configurations

devices/home-server/configuration.nix

@@ -0,0 +1,107 @@
+{ ... }:
+{
+  imports = [ ./hardware-configuration.nix ];
+
+  nix.settings.experimental-features = [
+    "nix-command"
+    "flakes"
+  ];
+
+  services = {
+    adguardhome = {
+      enable = true;
+      port = 34778;
+      openFirewall = true;
+    };
+
+    fail2ban = {
+      enable = true;
+      ignoreIP = [
+        "192.168.0.0/16"
+      ];
+    };
+
+    cloudflare-dyndns = {
+      enable = true;
+      apiTokenFile = "/home/asakiyuki/.secret/CLOUDFLARE_TOKEN_KEY";
+      frequency = "*:0/5";
+      proxied = true;
+      ipv6 = false;
+      ipv4 = true;
+      deleteMissing = false;
+      domains = [ "ddns.asakiyuki.com" ];
+    };
+
+    openssh = {
+      enable = true;
+      ports = [ 15523 ];
+      authorizedKeysInHomedir = true;
+      authorizedKeysFiles = [ "/home/asakiyuki/.ssh/authorized_keys" ];
+      settings = {
+        AllowUsers = [
+          "asakiyuki"
+          "junko"
+        ];
+        PasswordAuthentication = true;
+        KbdInteractiveAuthentication = false;
+        AllowAgentForwarding = false;
+        AllowStreamLocalForwarding = false;
+        X11Forwarding = false;
+        PermitRootLogin = "no";
+      };
+    };
+  };
+
+  networking = {
+    useDHCP = false;
+    networkmanager.enable = true;
+    defaultGateway = "192.168.1.1";
+    nameservers = [
+      "8.8.8.8"
+      "1.1.1.1"
+    ];
+
+    interfaces = {
+      enp1s0 = {
+        useDHCP = false;
+
+        ipv4.addresses = [
+          {
+            address = "192.168.1.100";
+            prefixLength = 24;
+          }
+        ];
+
+        ipv6.addresses = [
+          {
+            address = "2402:800:62d0:1c26:abcd:1234:5678:9abc";
+            prefixLength = 64;
+          }
+        ];
+      };
+    };
+
+    firewall = {
+      enable = true;
+      allowedUDPPorts = [
+        53
+        34778
+      ];
+      allowedTCPPorts = [
+        15523
+        53
+        8443
+        583
+        25565
+      ];
+    };
+  };
+
+  nixpkgs.config.allowUnfree = true;
+
+  boot.loader.systemd-boot.enable = true;
+  boot.loader.efi.canTouchEfiVariables = true;
+
+  time.timeZone = "Asia/Ho_Chi_Minh";
+  system.stateVersion = "25.11";
+}