fix avahi

modules/nixos/network/default.nix

@@ -122,6 +122,14 @@ in
       network.wait-online.enable = false;
     };
 
+    # Restrict Avahi to the configured LAN interface when one is explicitly set.
+    # This prevents Avahi from announcing on virtual/container interfaces (veth*,
+    # podman0, virbr0, etc.) which causes hostname conflicts and suffix mangling
+    # (e.g. "jallen-nas-4.local" instead of "jallen-nas.local").
+    services.avahi = lib.mkIf (cfg.ipv4.interface != "") {
+      allowInterfaces = [ cfg.ipv4.interface ];
+    };
+
     networking = {
       hostName = lib.mkForce cfg.hostName;