Nagios Support Forum

Hi all

Running 2024R1.4.1 on Ubuntu 22.04

I've got numerous Windows and Linux (RHEL/Ubuntu) hosts, most of these are showing performance graph data normally for CPU Usage, Memory Usage, etc. but some Ubuntu hosts are not.

The usage is shown live, but no historic data is visible. Ie. On the Performance graphs tab the graphs show 'No data to display', but the gauges at the bottom show accurate values.

The hosts have been in place on the NagiosXI server since it was migrated from a CentOS box a year or two ago. I honestly don't know if it was once working and now stopped, or has never worked.

I've spotted 2 hosts with the issue thus far, nothing obvious that distinguishes them from the other hosts. Both are Ubuntu, but plenty of other Ubuntu hosts working fine.

I do have files being created in /usr/local/nagios/var/spool/perfdata and npcd is running, albeit with some warning messages showing in systemctl status
Appreciate any pointers on where to look! The suggestions I've seen on the forum mostly seem to concern situations where all hosts are failing to record performance data.

locate the perfdata dir and look under the host dirs at the service dirs and files in them. If the files aren't being updated move or delete them.

Thank you kg!

I've located perf data under /usr/local/nagios/share/perfdata/ and I've got a dir for My-Host. Inside there I've got XMLs and RRD files for each service.

The RRD files for the problem services weren't being updated (though the XMLs were) so I've moved those and rebooted the box (not sure that was necessary...).

New RRD files have been created and are populating. Will give it a few hours and check if the graphs updating, but looks good!

Is there a way to monitor/alert for these files being unchanged within Nagios itself, other than just having a cron job looking for RRD files with old timestamps?

It sounds like a partial performance data processing issue. Since live data is showing but historical data is missing, you might want to check if the affected hosts have any issues with perfdata processing. Verify that npcd is running without errors and check the logs (/usr/local/nagios/var/npcd.log and /usr/local/nagios/var/perfdata.log). Also, confirm that RRD and XML files are being updated in /usr/local/nagios/share/perfdata/. Hope this helps.

Thanks Marucs, RRD files not being updated for a number of hosts, cleared those out and all working now. WIll setup a cron job to keep an eye on them