When I try to run a command on a host, I get this in a window that pops up. I have checked and the file is there and goes away when nagios is stopped and comes back. I have done a few google searches and found a few hits on this and the permissions, etc appear to be in line with those discussions I found but still have this issue.
/usr/local/nagios/var/rw/nagios.cmd does not exist.
I think you said so but to be clear, does /usr/local/nagios/var/rw/nagios.cmd exist? If so do an ls -l on it and show me the full output? I am curious about the permissions, owner, and group on the file.
Also, when I use N2C to import hosts, I click on a hostgroup and select a template and the progress bar completes about importing 7 hosts but none are imported. The import results has no check marks or messages, just the host names on left column.
Go to Settings->NPC and set log level to Debug. The cacti log should be set to LOW so there is nopt to many logs to parse through. With NPC in Debug try to do another import, then shut off NPC Debug (dont forget to shut it off).
Also before doing the import get a tail going on your apache httpd logs. Look for any errors or fatals.
For your graph issue the graph is supposed to display in the popup window. Lets hit the first two issues above first then we can tackle this. As an FYI... Once I get done with the performance enhancements I am working on I am going to revisit importing and graphing.