cacti / unbound / Result from CMD not valid. Partial Result

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The latest release of unbound (1.8.3) contain the instructions to use the unbound statistics in cacti.
I've successfully managed to get the data into seven files, updated every five minutes, using cron.

I've imported the unbound template, using the command:
sudo php /usr/share/cacti/cli/import_template.php --filename="/home/pi/unbound/unbound-1.8.3/contrib/unbound-cacti/Host template (all in one)/cacti_host_template_unbound_dns.xml" --with-template-rras
This appears to be successful, the template is available in the cacti interface
I've created a graph, using the command:
sudo php /usr/share/cacti/cli/add_graphs.php --host-id=1 --graph-type=cg --graph-template-id=35
This appears to be successful, the graph is visible on the graphs tab of the cacti web site.
However …
The available data never appears in the graph.
all logs except cacti.log are empty. The cacti log contains two entries, repeated every 5 minutes:
CMDPHP: Poller[0] Host[1] DS[29] WARNING: Result from CMD not valid. Partial Result: U
SYSTEM STATS: Time:0.4753 Method:cmd.php Processes:1 Threads:N/A Hosts:2 HostsPerProcess:2 DataSources:5 RRDsProcessed:5
Running the command sudo php /usr/share/cacti/site/cmd.php doesn't provide any aditional info, output:
CMDPHP: Poller[0] Host[1] DS[29] WARNING: Result from CMD not valid. Partial Result: U
CMDPHP: Poller[0] Time: 0.1108 s, Theads: N/A, Hosts: 1

Duckduckgo doesn't provide any help to solve this problem.
Anybody???
Thanks for your time and effort

[netniV]

This is going to be file permissions. You've run the import as root which means any files created will be as root.

Running CMD.PHP directly is not advised because that is run by poller.php itself.