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Prerequisites

We expect that the following rules are set up in Setup > Services > Service monitoring rules > Configuration of RRD databases of services:

And Setup > Hosts > Host monitoring rules > Configuration of RRD databases of hosts:

Problem

After converting the RRD files to the new format (described in this manual), in some rare cases, it might happen that data is still written to {{$OMD_ROOT/var/pnp4nagios/perfdata/myhost/}}.

At the same time, you might see error messages in the cmc.log like:

2021-09-20 09:18:14 [4] [rrdcached thread] [rrdcached at "/omd/sites/mysite/tmp/run/rrdcached.sock"] [log] -1 No such file: /omd/sites/mysite/var/pnp4nagios/perfdata/myhost/Memory_and_pagefile_pagefile_total.rrd
2021-09-20 09:18:14 [4] [rrdcached thread] [rrdcached at "/omd/sites/mysite/tmp/run/rrdcached.sock"] [log] -1 No such file: /omd/sites/mysite/var/pnp4nagios/perfdata/myhost/Memory_and_pagefile_pagefile_avg.rrd
2021-09-20 09:18:14 [4] [rrdcached thread] [rrdcached at "/omd/sites/mysite/tmp/run/rrdcached.sock"] [log] -1 No such file: /omd/sites/mysite/var/pnp4nagios/perfdata/myhost/Power_cpu0_Cores_w.rrd
2021-09-20 09:18:14 [4] [rrdcached thread] [rrdcached at "/omd/sites/mysite/tmp/run/rrdcached.sock"] [log] -1 No such file: /omd/sites/mysite/var/pnp4nagios/perfdata/myhost/Power_cpu0_DRAM_w.rrd
2021-09-20 09:18:14 [4] [rrdcached thread] [rrdcached at "/omd/sites/mysite/tmp/run/rrdcached.sock"] [log] -1 No such file: /omd/sites/mysite/var/pnp4nagios/perfdata/myhost/Power_cpu0_Graphics_w.rrd
2021-09-20 09:18:14 [4] [rrdcached thread] [rrdcached at "/omd/sites/mysite/tmp/run/rrdcached.sock"] [log] -1 No such file: /omd/sites/mysite/var/pnp4nagios/perfdata/myhost/Power_cpu0_Package_w.rrd

You can notice that some RRD files in {{$OMD_ROOT/var/pnp4nagios/perfdata/myhost/}} are still updated. The chances are high that not all hosts are affected, but only a few, even less than 10%.

Solution

1. Change to the site user and stop the site:

   
   

   Code Block
   language bash theme RDark
   su mysite OMD[mysite]:~ omd stop

   .

2. Run the following command for one of the affected hosts:

   Code Block
   language bash theme RDark
   OMD[mysite]:~ cmk -vv --convert-rrds --delete-rrds myhost

   .

3. If such messages appear like these:

   Code Block
   language bash theme RDark
   HOST_ PNP -> CMC WARNING: XML /opt/omd/sites/mysite/var/pnp4nagios/perfdata/myhost/_HOST_.xml refers to not existing RRD /opt/omd/sites/mysite/var/pnp4nagios/perfdata/myhost/_HOST__rta.rrd. Nothing to convert. Cleanup the XML file manually in case this is OK.

   .

4. You can delete the XML file.
   .
5. Start the site and the RRD files should be written correctly now:

   
   

   Code Block
   language bash theme RDark
   OMD[mysite]:~ omd start

   .

6. If it works, you can run that for every host separately, as shown above, or for all hosts, with the below command:

   Note
   Please make sure that the site is stopped before running the command to convert and delete the rrds

   
   

   Code Block
   language bash theme RDark
   OMD[mysite]:~ cmk -vv --convert-rrds --delete-rrds

   
   

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