hosts/backup-4: Replicate backup to palladium

hosts/palladium/restic-server.nix

@@ -0,0 +1,20 @@
+{ ... }:
+
+{
+  services.restic.server = {
+    enable = true;
+    privateRepos = true;
+    dataDir = "/data/backup";
+    listenAddress = "[::]:43242";
+  };
+
+  # restic rest server does not support --htpasswd-file in the current version of nixpkgs
+  # until then we copy the secrets to the common location
+  sops.secrets.restic-server-backup-htpasswd = {
+    path = "/data/backup/.htpasswd";
+    owner = "restic";
+    group = "restic";
+  };
+
+  networking.firewall.interfaces.wg-b-palladium.allowedTCPPorts = [ 43242 ];
+}