How to create threshold from CDE Function value

[kashif]

Hi everyone,
This is my first post. We are using Cacti 0.8.7g along with Thold version .5.

Threshold are working fine for values which are receiving through data template or Data input method etc.

Now problem is that We want to create threshold for Total value of all DNS queries type. And this value in the graph Template is calculating by CDE function " Total All Data source" This value does not become available when we try to create the threshold. Any body can help in this regard.