diff --git a/clanModules/zerotier/README.md b/clanModules/zerotier/README.md
index c82f8c1f1..7f150538e 100644
--- a/clanModules/zerotier/README.md
+++ b/clanModules/zerotier/README.md
@@ -2,8 +2,10 @@
 description = "Configures [Zerotier VPN](https://zerotier.com) secure and efficient networking within a Clan.."
 features = [ "inventory" ]
 
-constraints.roles.controller.eq = 1
-constraints.roles.moon.max = 7
+[constraints]
+roles.controller.min = 1
+roles.controller.max = 1
+roles.moon.max = 7
 ---
 
 ## Overview
diff --git a/clanModules/zerotier/shared.nix b/clanModules/zerotier/shared.nix
index 2b5de214e..7f5b13d22 100644
--- a/clanModules/zerotier/shared.nix
+++ b/clanModules/zerotier/shared.nix
@@ -48,7 +48,7 @@ in
       # TODO: This should also be checked via frontmatter constraints
       {
         assertion = builtins.length instanceNames == 1;
-        message = "The zerotier module currently only supports one instance per machine, but found ${builtins.toString instanceNames}";
+        message = "The zerotier module currently only supports one instance per machine, but found ${builtins.toString instanceNames} on machine ${config.clan.core.machineName}";
       }
     ];
 
diff --git a/inventory.json b/inventory.json
index ebc3ec114..cda90d888 100644
--- a/inventory.json
+++ b/inventory.json
@@ -17,7 +17,7 @@
   },
   "services": {
     "zerotier": {
-      "1": {
+      "one": {
         "roles": {
           "controller": {
             "machines": ["test-inventory-machine"]