How does Nagios Core store the log data ?

[ola]

Hello,

how is the data stored for graphs etc. ? Is it log files/database ?
Thank you very much

[mcapra]

In your nagios.cfg file, the following directives are relevant:
host_perfdata_file
service_perfdata_file

The historical data used for graphing is stored in Round Robin Databases created by RRDTool and is generally located at /usr/local/nagios/share/perfdata.