## Debugging Configuration Errors <a id="script-debugger-config-errors"></a>
The following example illustrates the problem of a service [apply rule](03-monitoring-basics.md#using-apply-for)
-which expects a dictionary value for `config`, but the host custom attribute only
+which expects a dictionary value for `config`, but the host custom variable only
provides a string value:
```
In order to analyse these server-side errors, you can use the script debugger.
-The following example tries filter for all host objects where the custom attribute
+The following example tries filter for all host objects where the custom variable
`os` is set. There are various possibilities to check that, one of them would be
`host.vars.os != ""`. Another idea is to use the [contains](18-library-reference.md#dictionary-contains) method on the custom
attribute dictionary like this: `host.vars.contains("os")`.
-d '{ "filter": "host.vars.contains(\"os\")", "attrs": [ "__name" ], "joins": [ "host.name", "host.vars" ], "pretty": true }'
```
-This will fail on all hosts which don't have any custom attribute specified.
+This will fail on all hosts which don't have any custom variable specified.
```
# icinga2 daemon -X