I'm seeing this issue for a several different graphs that I've experimented with. These are standard Cacti templates. A typical example is what I see with "ucd/net - CPU Usage." Two of the three .rrd files are getting created; nice and user. The system .rrd is not.
I've manually run the Data Source Debug output from all three. Two work, the third does not. The .rrd file is NOT created. This is true whether I do it as root or the cactiuser (apache in my case). The really frustrating part is that there is no error message generated by rrdtool.
The weird part is that I can't even create the file by dropping to a system console and typing 'touch rra/filename'. The same thing happens there. There was no error message generated, so I expected to see an empty file. Nope, nada. Again, this was the result whether I ran the command as root or as cactiuser. (This does work for the variables that rrdtool can create files for, though)
No error messages that look relevant in the Apache error log, either.
Does anyone have any idea what I should be looking for? Any further information that you might want?
Output from Data Source Debug for System:
----/usr/bin/rrdtool create \
/var/www/localhost/htdocs/cacti/rra/llama_cpu_system_39.rrd \
--step 300 \
DS:cpu_system:COUNTER:600:0:500 \
RRA:AVERAGE:0.5:1:600 \
RRA:AVERAGE:0.5:6:700 \
RRA:AVERAGE:0.5:24:775 \
RRA:AVERAGE:0.5:288:797 \
RRA:MAX:0.5:1:600 \
RRA:MAX:0.5:6:700 \
RRA:MAX:0.5:24:775 \
RRA:MAX:0.5:288:797 \
I don't know why, but things started magically working after I re-ran the debug output as apache. I'll take it!