Modify the variable name.

cookbooks/consul/templates/etc/consul.d/server.hcl.erb

@@ -11,9 +11,9 @@ acl {
   enable_token_persistence = true
 
   tokens {
-    master  = "<%= @manager_hosts %>"
-    agent   = "<%= @manager_hosts %>"
-    default = "<%= @manager_hosts %>"
+    master  = "<%= @server_token %>"
+    agent   = "<%= @server_token %>"
+    default = "<%= @server_token %>"
   }
 }