diff --git a/modules/clan/phonebox/default.nix b/modules/clan/phonebox/default.nix
index 6cde7801..0da576a6 100644
--- a/modules/clan/phonebox/default.nix
+++ b/modules/clan/phonebox/default.nix
@@ -287,7 +287,7 @@
                 dhcp-range = [
                   "192.168.254.100,192.168.254.100,255.255.255.0,3m"
                 ];
-                dhcp-leasefile = "/dev/null";
+                leasefile-ro = true;
                 dhcp-option = [
                   "3,192.168.254.1"
                 ];