Graph not update

[Alexz.]

Hello to all...
we have a problem in my cacti...yestarday we disable the poller (it make about 50 zombi process in my Linux Gentoo). Now, after enable the poller, graph it's not updating...Always NAN!!!
The SNMP are ok but the graph it's empty (NAN value).
If i see the last modify data for RRD file it wasn't update.... any suggest?
I'he try to enable the debug but no error!!!

some info:
Maximum Threads per Process 1
Maximum Concurrent Poller Processes 1
Poller Type: cmd.php

Thank.
Ale

[gandalf]

Please find a generic debugging procedure at the second link of my signature
Reinhard