The following overview shows all of the important files and directories applicable
to the Checkmk micro core. All data paths relate to the instance’s home directory.
For example: if an instance is named
mysite, then all of the paths are
1. Runtime data
Here messages from starting and stopping the CMC can be found, as well as general warnings and error messages. The history for hosts and services (with Nagios, both are in
Directory with all CMC runtimes.
The core’s configuration. In Nagios this data equates to the data sets under
The core’s current runtime state. This stores information on the current status of hosts and services, likewise downtimes, acknowledgements and commentaries. This data equates to the
Backup copies of the status following a migration from an old CMC version, or when the CMC detects a large reduction in the number of hosts in the configuration. Thus you can return to the old status (and recover its downtimes and acknowledgements), e.g., if due to a configurations-error all hosts have been temporarily removed from the monitoring.
The history for all hosts and services is stored in text format in this file. This corresponds in its content and format to the
Old versions of
The CMC’s livestatus socket. This is in the same location as in Nagios. Because the CMC is livestatus-compatible with Nagios and Icinga, all extensions based on livestatus can be used without modification (e.g. NagVis).
The CMC’s current process-ID
The CMC has no configuration data of its own. All settings for the CMC can be found
in the Global Settings WATO module under
Monitoring Core, and these are stored together with the other global options in
The executable program for the CMC itself. This has been developed in C, and apart from the standard C library requires no other libraries (in particular, no Boost). For testing purposes one can also activate the CMC by hand (Try it:
A help process that is started several times by the CMC, and which takes over the efficient running of checks.
A help process that is started by the CMC and which takes over the sending of ICMP packages for the Smart-Ping. This MUST be installed with SUID-root.
A help process that is started by the CMC and which takes over the receiving of ICMP and TCP connection packages for the Smart-Ping. This MUST be installed with SUID-root.
The Micro Core’s start script
WATO extension with global settings and rule sets for the CMC.
A Sidebar plug-in for Multisite with CMC performance data.
Checkmk module that generates the configuration for the CMC.
Checkmk module for installing RRD data.